[Illustration: images/cover.jpg]

* * *

#  FLOWERS

AND THEIR PEDIGREES

## BY

GRANT ALLEN

###### AUTHOR OF

'COLIN CLOUT'S CALENDAR' 'VIGNETTES FROM NATURE'

ETC.

[Illustration: images/titlepage.jpg]

### NEW YORK:

D. APPLETON AND COMPANY,

1902.

* * *

## PREFACE.

These little essays originally appeared as articles in 'Longman's
Magazine,' the 'Cornhill Magazine,' 'Macmillan's Magazine,' the
'Gentleman's Magazine,' and 'Belgravia,' and I have to thank the editors
and proprietors of those periodicals for kind permission to reprint them
here. They are now offered to the public as a first instalment of a work
which I hope some day more fully to carry out--a Functional Companion to
the British Flora. We know by this time pretty well what our English
wild flowers are like: we want to know next why they are just what they
are, and how they came to be so.

G. A.

Lyme, Dorset:

_July 1883_.

* * *

## CONTENTS.

PAGE

INTRODUCTORY

1

I.

THE DAISY'S PEDIGREE

6

II.

THE ROMANCE OF A WAYSIDE WEED

44

III.

STRAWBERRIES

80

IV.

CLEAVERS

100

V.

THE ORIGIN OF WHEAT

133

VI.

A MOUNTAIN TULIP

173

VII.

A FAMILY HISTORY

197

VIII.

CUCKOO-PINT

236

* * *

## FLOWERS AND THEIR PEDIGREES.

* * *

## _INTRODUCTORY._

Our beautiful green England is carpeted, more than any other country in
the world, perhaps, save only Switzerland and a few other mountain
lands, with a perpetual sward of vivid verdure, interspersed with
innumerable colours of daisies, and buttercups, and meadow-sweet, and
harebells, and broader patches of purple heather. It is usual to speak
of tropical vegetation, indeed, with a certain forced ecstasy of
language; but those who know the tropics best, know that, though you may
find a few exceptionally large and brilliant blossoms here and there
under the breadth and shade of equatorial forests, the prevailing tone
is one of monotonous dry greenery; and there is nothing anywhere in very
southern climes to compare, as to mass of colour, with our Scotch hill-
sides, our English gorse-clad commons, or our beautiful dappled meadows
and cornfields, all aglow with the infinite wealth of poppies,
bluebottles, foxgloves, ox-eye daisies, and purple fritillaries. The
Alps alone can equal the brilliant colouring of our own native British
flora. Poor as it is in number of species--a mere isolated fragment of
the wider European groups--it can fearlessly challenge the rest of the
whole world in general mingled effect of gaiety and luxuriance.

Now, every one of these English plants and weeds has a long and eventful
story of its own. In the days before the illuminating doctrine of
evolution had been preached, all we could say about them was that they
possessed such and such a shape, and size, and colour: and if we had
been asked why they were not rounder or bigger or bluer than they
actually are, we could have given no sufficient reason, except that they
were made so. But since the great principle of descent with modification
has reduced the science of life from chaos to rational order, we are
able to do much more than that. We can now answer confidently: Such and
such a plant is what it is in virtue of such and such ancestral
conditions, and it has been altered thus and thus by these and those
variations in habit or environment. Every plant or animal, therefore,
becomes for us a puzzle to be explained, a problem to be solved, a
hieroglyphic inscription to be carefully deciphered. In the following
pages, I have taken some half-dozen of familiar English weeds or
flowers, and tried thus to make them yield up the secret of their own
origin. Each of them is ultimately descended from the common central
ancestor of the entire flowering group of plants; and each of them has
acquired every new diversity of structure or appearance for some
definite and useful purpose. As a rule, traces of all the various stages
through which every species has passed are still visibly imprinted upon
the very face of the existing forms: and one only requires a little care
and ingenuity, a little use of comparison and analogy, to unravel by
their own aid the story of their own remoter pedigree. This is the
method which I have here followed in the papers that deal with the
various modifications of the daisy, of the grasses, of the lilies, of
the strawberry, and of the whole rose family.

Again, not only has each English plant a general history as a species,
but it has also a separate history as a member of the British flora.
Besides the question how any particular flower or fruit came to exist at
all, we have to account for the question how it came to exist here and
now in this, that, or the other part of the British Islands. For, of
course, all plants are not to be found in all parts of the world alike,
and their distribution over its surface has to be explained on
historical grounds just as a future ethnologist would have to explain
the occurrence of isolated French communities in Lower Canada and
Mauritius, of African negroes in Jamaica and Brazil, or of Chinese
coolies in San Francisco and the Australian colonies. In this respect,
our English plants open out a series of interesting problems for the
botanical researcher; because we happen to possess a very mixed and
fragmentary flora, made up to a great extent of waifs and strays from at
least three large distinct continental groups, besides several casual
colonists. Thus while at Killarney we get a few rare Spanish or
Portuguese types, in Caithness and the Highlands we get a few rare
Alpine or Arctic types: and while in Norfolk and Suffolk we find some
central European stragglers, the ponds of the Hebrides are actually
occupied by at least one American pond-weed, its seeds having been
wafted over by westerly breezes, or carried unconsciously by water-birds
in the mud and ooze which clung accidentally to their webbed feet.
Moreover, we know that at no very remote period, geologically speaking,
Britain was covered by a single great sheet of glaciers, like that which
now covers almost all Greenland: and we may therefore conclude with
certainty that every plant at present in the country has entered it from
one quarter and another at a date posterior to that great lifeless
epoch. This, then, gives rise to a second set of problems, the problems
connected with the presence in England of certain stray local types,
Alpine or Arctic, Southern or Transatlantic, European or Asiatic.
Questions of this sort I have raised and endeavoured to answer with
regard to two rare English plants in the papers on the hairy spurge and
the mountain tulip.

In short, these little essays deal, first with the evolution of certain
plant types in general; and secondly with their presence as naturalised
citizens of our own restricted petty insular floral commonwealth.

* * *

## I.

### _THE DAISY'S PEDIGREE._

[Illustration: images/i006.jpg]

Fig. 1.--The Common Daisy.

Have you ever paused for a moment to consider how much man loses for
want of that microscopic eye upon whose absence complacent little Mr.
Pope, after his optimistic fashion, was apparently inclined rather to
congratulate his fellow-beings than otherwise? What a wonderful world we
should all live in if only we could see it as this little beetle here
sees it, half buried as he is in a mighty forest of luxuriant tall green
moss! Just fancy how grand and straight and majestic those slender
sprays must look to him, with their waving, feathery branches spreading
on every side, a thousand times more gracefully than the long boughs of
the loveliest tropical palm trees on some wild Jamaican hill-side. How
quaint the tall capsules must appear in his eyes--great yellow seed-
vessels nearly as big as himself, with a conical, pink-edged hood, which
pops off suddenly with a bang, and showers down monstrous nuts upon his
head when he passes beneath. Gaze closely into the moss forest, as it
grows here beside this smooth round stone where we are sitting, and
imagine you can view it as the beetle views it. Put yourself in his
place, and look up at it towering three hundred feet above your head,
while you vainly strive to find your way among its matted underbrush and
dense labyrinths of close-grown trunks. Then just look at the mighty
monsters that people it. The little red spider, magnified to the size of
a sheep, must be a gorgeous and strange-looking creature indeed, with
his vivid crimson body and his mailed and jointed legs. Yonder neighbour
beetle, regarded as an elephant, would seem a terrible wild beast in all
seriousness, with his solid coat of bronze-burnished armour, his huge
hook-ringed antennæ, and his fearful branched horn, ten times more
terrible than that of a furious rhinoceros charging madly through the
African jungle. Why, if you will only throw yourself honestly into the
situation, and realise that awful life-and-death struggle now going on
between an ant and a May-fly before our very eyes, you will see that
Livingstone, and Serpa Pinto, and Gordon Cumming are simply nowhere
beside you: that even Jules Verne's wildest story is comparatively tame
and commonplace in the light of that marvellous miniature forest. Such a
jumble of puzzle-monkeys, and bamboos, and palms, and banyan trees, and
crags, and roots, and rivers, and precipices was never seen; inhabited
by such a terrible and beautiful phantasmagoria of dragons, hippogriffs,
unicorns, rocs, chimæras, serpents, and wyverns as no mediæval fancy
ever invented, no Greek mythologist ever dreamt of, and no Arabian
story-teller ever fabled. And yet, after all, to our clumsy big eyes, it
is but a little patch of familiar English grass and mosses, crawled over
by half a dozen sleepy slugs and long-legged spiders, and slimy
earthworms.

Still, if you so throw yourself into the scene, you cannot avoid
carrying your own individuality with you into the beetle's body. You
fancy him admiring that fairy landscape as you would admire it were you
in his place, provided always you felt yourself quite secure from the
murderous jaws and hooked feet of some gigantic insect tiger lurking in
the bristly thicket behind your back. But, as a matter of fact, I
greatly doubt whether the beetle has much feeling for beauty of scenery.
For a good many years past I have devoted a fair share of my time to
studying, from such meagre hints as we possess, the psychology of
insects: and on the whole I am inclined to think that, though their
æsthetic tastes are comparatively high and well-developed, they are, as
a rule, decidedly restricted in range. Beetles and butterflies only seem
to admire two classes of visible objects--their own mates, and the
flowers in which they find their food. They never show much sign of
deliberate love for scenery generally or beautiful things in the
abstract outside the limits of their own practical life. If this seems a
narrow æsthetic platform for an intelligent butterfly, one must remember
that our own country bumpkin has perhaps a still narrower one; for the
only matter in which he seems to indulge in any distinct æsthetic
preference, to exercise any active taste for beauty, is in the choice of
his sweetheart, and even there he is not always conspicuous for the
refinement of his judgment. But there is a way in which one can really
to some extent throw oneself into the mental attitude of a human being
reduced in size so as to look at the moss-forest with the eye of a
beetle, while retaining all the distinctive psychological traits of his
advanced humanity: and that is by making himself a microscopic eye with
the aid of a little pocket-lens. Even for those who do not want to use
one scientifically, it opens a whole universe of new and delightful
scenery in every tuft of grass and every tussock of wayside weeds; and
by its aid I hope to show you this morning how far the eyes and æsthetic
tastes of insects help us to account for the pedigree of our familiar
childish friend, the daisy. No fairy tale was ever more marvellous, and
yet certainly no fairy tale was ever half so true.

I propose then, to-day, to dissect one of these daisies with my little
knife and glass, and unravel, if I can, the tangled skein of causes
which have given it its present shape, and size, and colour, and
arrangement. If you choose, you can each pick a daisy for yourselves,
and pull it to pieces as I go along, to check off what I tell you; but
if you are too lazy, or can't find one within reach, it doesn't much
matter; for you can at least carry the picture of so common a flower
well enough in your mind's eye to follow what I have to say without one:
and that is all that is at all necessary for my present purpose.

The question as to how the daisy came to be what it is, is comparatively
a new one. Until a short time ago everybody took it for granted that
daisies had always been daisies, cowslips always cowslips, and primroses
always primroses. But those new and truer views of nature which we owe
to Mr. Darwin and Mr. Herbert Spencer have lately taught us that every
plant and every animal has a long history of its own, and that this
history leads us on through a wonderful series of continuous
metamorphoses compared with which Daphne's or Arethusa's were mere
single episodes. The new biology shows us that every living thing has
been slowly moulded into its existing shape by surrounding
circumstances, and that it bears upon its very face a thousand traces of
its earlier stages. It thus invests the veriest weed or the tiniest
insect with a fresh and endless interest: it elevates them at once into
complex puzzles for our ingenuity--problems quite as amusing and ten
times as instructive as those for whose solution the weekly papers offer
such attractive and unattainable prizes. What is the meaning of this
little spur? How did it get that queer little point? Why has it
developed those fluffy little hairs? These are the questions which now
crop up about every part of its form or structure. And just as surely as
in surveying England we can set down Stonehenge and Avebury to its
prehistoric inhabitants, Watling Street and the Roman Wall to its
southern conquerors, Salisbury and Warwick to mediæval priests and
soldiers, Liverpool and Manchester to modern coal and cotton--just so
surely in surveying a flower or an insect can we set down each
particular point to some special epoch in its ancestral development.
This new view of nature invests every part of it with a charm and hidden
meaning which very few among us have ever suspected before.

Pull your daisy to pieces carefully, and you will see that, instead of
being a single flower, as we generally suppose at a rough glance, it is
in reality a whole head of closely packed and very tiny flowers seated
together upon a soft fleshy disk. Of these there are two kinds. The
outer florets consist each of a single, long, white, pink-tipped ray,
looking very much like a solitary petal: the inner ones consist each of
a small, golden, bell-shaped blossom, with stamens and pistil in the
centre, surrounded by a yellow corolla much like that of a Canterbury
bell in shape, though differing greatly from it in size and colour. The
daisy, in fact, is one of the great family of Composites, all of which
have their flowers clustered into similar dense heads simulating a
single blossom, and of which the sunflower forms perhaps the best
example, because its florets are quite large enough to be separately
observed even by the most careless eye.

[Illustration: images/i013.jpg]

Fig. 2.--Ray floret of Daisy. 
Fig. 3.--Central floret of Daisy.

Now, if you look closely at one of the central yellow florets in the
daisy, you will see that its edge is vandyked into four or five separate
pointed teeth exactly like those of the Canterbury bell. These teeth
clearly point back to a time when the ancestors of the daisy had five
separate petals on each flower, as a dog-rose or a May-blossom still
has. Again, before the flowers of the daisy had these five separate
petals, they must have passed through a still earlier stage when they
had no coloured petals at all. And as it is always simpler and easier to
recount history in its natural order, from the first stages to the last,
rather than to trace it backward from the last to the first, I shall
make no apology for beginning the history of the daisy at the beginning,
and pointing out as we go along the marks which each stage has left upon
its present shape or its existing arrangement and colour.

[Illustration: images/i015.jpg]

Fig. 4.--Longitudinal section of Common Buttercup.

The very earliest ancestor of the daisy, then, with which we need deal
to-day, was an extremely simple and ancient flower, hardly recognisable
as such to any save a botanical eye. And here I must begin, I fear, with
a single paragraph of rather dull and technical matter, lest you should
miss the meaning of some things I shall have to tell you in the sequel.
If you look into the middle of a buttercup or a lily you know that you
will see certain little yellow spikes and knobs within the petals, which
form a sort of central rosette, and look as if they were put there
merely to give finish and completeness to the whole blossom. But in
reality these seemingly unimportant spikes and knobs are the most
important parts, and the only indispensable parts, of the entire flower.
The bright petals, which alone are what we generally have in our minds
when we think of flowers, are comparatively useless and inessential
organs: a vast number of flowers have not got them at all, and, in those
which have got them, their purpose is merely subsidiary and
supplementary to that of the little central spikes and knobs. For the
small yellow rosette consists of the stamens and pistils--the 'essential
floral organs,' as botanists call them. A flower may be complete with
only a single stamen or a single pistil, apart from any petals or other
bright and conspicuous surroundings; and some of the simplest flowers do
actually consist of such separate parts alone: but without stamens and
pistils there can be no flower at all. The object of the flower, indeed,
is to produce fruit and seed, and the pistil is the seed-vessel in its
earliest form; while the stamen manufactures the pollen without which
the seeds cannot possibly be matured within the capsules. In some
species the stamens and pistils occur in separate flowers, or even on
separate plants; in others, the stamens and pistils occur on the same
plant or in the same flower, and this last is the case in almost all the
blossoms with which we are most familiar. But the fundamental fact to
bear in mind is this--that the stamens and pistils are the real and
essential parts of the flower, and that all the rest is leather and
prunella--mere outer decoration of these invariable and necessary
organs. The petals and other coloured adjuncts are, as I hope to show
you, nothing more than the ornamental clothing of the true floral parts;
the stamens and pistils are the living things which they clothe and
adorn. Now probably you know all this already, exactly as the readers of
the weekly reviews know by this time all about the personage whom we
must not describe as Charlemagne, or the beings whom it is a mortal sin
to designate as Anglo-Saxons. But then, just as there are possibly
people in the worst part of the East End who still go hopelessly wrong
about Karl and the Holy Roman Empire, and just as there are possibly
people in remote country parishes who are still the miserable victims of
the great Anglo-Saxon heresy, so, doubtless, there may yet be persons--
say in the western parts of Cornwall or the Isle of Skye--who do not
know the real nature of flowers; and these persons must not be wholly
contemned because they happen not to be so wise as we ourselves and the
_Saturday Review_. An eminent statistician calculates that Mr. Freeman
has demolished the truculent Anglo-Saxon in 970 several passages, and
yet there are even now persons who go on firmly believing in that
mythical being's historical existence. And the moral of that is this, as
the Duchess would say, that you should never blame any one for telling
you something that you knew before; for it is better that ninety-nine
wise men should be bored with a twice-told tale, than that one innocent
person should be left in mortal error for lack of a short and not wholly
unnecessary elementary explanation.

[Illustration: images/i019.jpg]

Fig. 5.--Frond and flower of Duckweed.

The simplest and earliest blossoms, then--to return from this didactic
digression--were very small and inconspicuous flowers, consisting,
probably, of a single stamen and a single pistil each. Of these simplest
and earliest forms a few still luckily survive at the present day; for
it is one of the rare happy chances in this queerly ordered universe of
ours that evolution has almost always left all its footmarks behind it,
visibly imprinted upon the earth through all its ages. When any one form
develops slowly into another, it does not generally happen that the
parent form dies out altogether: on the contrary, it usually lingers on
somewhere, in some obscure and unnoticed corner, till science at last
comes upon it unawares, and fits it into its proper place in the scale
of development. We have still several fish in the very act of changing
into amphibians left in a few muddy tropical streams; and several
oviparous creatures in the very act of changing into mammals left in the
isolated continent of Australia; and so we have also many low,
primitive, or simple forms of plants and animals left in many stray
situations in every country. Amongst them are some of these earliest
ancestral flowers. On almost every wayside pond you will find all the
year round a green film of slimy duckweed. This duckweed is, as it were,
the Platonic idea of a flowering plant--the generic type common to them
all reduced to its simplest elements. It has no roots, no stem, no
branches, no visible blossom, no apparent seed; it consists merely of
solitary, roundish, floating leaves, budding out at the edge into other
leaves, and so spreading till it covers the whole pond. But if you look
closely into the slimy mass in summer time, you may be lucky enough to
catch the weed in flower--though not unless you have a quick eye and a
good pocket-lens. The flowers consist of one, and sometimes two, stamens
and a pistil, growing naked out of the edge of the leaf. No one but a
botanist could ever recognise their nature at all, for they all look
like mere yellowish specks on the slender side of the green frond; but
the pistil contains true seeds, and the stamens produce true pollen, and
from the botanical standpoint that settles the question of their floral
nature at once. They are, in fact, representatives of the simplest
original form of flower, preserved to our own day on small stagnant
ponds, where the competition of other plants does not press them hard as
it has pressed their congeners on dry land or in open lakes and
rivers.[1] From some such simple form as this we may be pretty sure that
all existing flowering plants are ultimately descended.

[Illustration: images/i021.jpg]

_a_, Carpels or ovaries; _b_, stamens; _c_, petals; _d_, calyx.

Fig. 6.--Diagram of primitive dicotyledonous flower.

In most modern flowers, however, each blossom contains several stamens
and several carpels (or pistil-divisions), and the way in which such a
change as this might come about can be easily imagined; for even in many
existing plants, where the separate flowers have only a single stamen or
a single pistil each, they are nevertheless so closely packed together
that they almost form a single compound flower, as in the case of the
bur-reed and the various catkins, not to mention the arum and the
spurge, where only a trained eye can make out the organic separateness.
I shall not trouble you much, however, with these earlier stages in the
development of the daisy, both because I shall describe them elsewhere
in part, _à propos_ of other subjects, and because the later stages are
at once more interesting and more really instructive. It must suffice to
say that at some very ancient period the ancestors of the daisy, and of
one half the other modern flowers, had acquired an arrangement of
stamens and pistils in groups of five, so that each compound flower had
as a rule a pistil of five or ten carpels, surrounded by a row of five
or ten stamens. And almost all their existing descendants still bear
obvious traces of this original arrangement in rows of fives. On the
other hand, the ancestors of our lilies, and of the other half of our
modern flowers, had about the same period acquired an arrangement in
rows of three. And of this other ternary arrangement all their existing
descendants still bear similar traces. In fact, most flowers at the
present day show clear signs of being derived either from the original
five-stamened or the original three-stamened blossom. I don't mean to
say that this is the only mark of distinction between the two great
groups: on the contrary, it is only a very minor one; but it is for our
present purpose the one of capital importance.

[Illustration: images/i022.jpg]

_a_, Carpels or ovaries; _b_, stamens, inner row; _c_, stamens, outer
row; _d_, petals; _e_, calyx.

Fig. 7.--Diagram of primitive monocotyledonous flower.

The very primitive five-parted common ancestor of the daisy, the rose,
the buttercup, and our other quinary flowers, was still an extremely
simple and inconspicuous blossom. It had merely green leaves and plain
flower-stems, surmounted by a row of five or ten stamens, inclosing five
or ten carpels. Perhaps beneath them there may have been a little row of
cup-shaped green bracts, the predecessors of the calyx which supports
all modern flowers; but of this we cannot be at all sure. At any rate,
it had no bright-coloured petals. The origin of these petals is due to
the eyes and selective tastes of insects; and we must look aside for a
moment at the way in which they have been produced, in order rightly to
understand the ancestry of the daisy.

No pistil ever grows into a perfect fruit or sets ripe and good seeds
until it is fertilised by a grain of pollen from a stamen of its own
kind. In some plants the pollen is simply allowed to fall from the
stamens on to the pistil of the same flower; but plants thus self-
fertilised are not so strong or so hearty as those which are cross-
fertilised by the pollen of another. The first system resembles in its
bad effect the habit of 'breeding in and in' among animals, or of too
close intermarriages among human beings; while the second system
produces the same beneficial results as those of cross-breeding, or the
introduction of 'fresh blood' in the animate world. Hence, any early
plants which happened to be so constituted as to allow of easy cross-
fertilisation would be certain to secure stronger and better seedlings
than their self-fertilised neighbours; and wherever any peculiar form or
habit has tended to encourage this mode of setting seeds, the plants
have always prospered and thriven exceedingly in the struggle for
existence with their less fortunate congeners. A large number of flowers
have thus become specially adapted for fertilisation by the wind, as we
see in the case of catkins and grasses, where the stamens hang out in
long pendulous clusters, and the pollen is easily wafted by the breeze
from their waving filaments to the pistils of surrounding flowers. In
such cases as these, the stamens are generally very long and mobile, so
that the slightest breath shakes them readily; while the sensitive
surface of the pistil is branched and feathery, so as readily to catch
any stray passing grain of wind-borne pollen.

But there are other flowers which have adopted a different method of
getting the pollen conveyed from one blossom to another, and this is
upon the heads and legs of honey-eating insects. From the very first,
insects must have been fond of visiting flowers for the sake of the
pollen, which they used to eat up without performing any service to the
plant in return, as they still feloniously do in the case of several
wind-fertilised species; and to counteract this bad habit on the part of
their unbidden guests, the flowers seem to have developed a little store
of honey (which the insects prefer to pollen), and thus to have turned
their visitors from plundering enemies into useful allies and friends.
For even the early pollen-eaters must often unintentionally have
benefited the plant, by carrying pollen on their heads and legs from one
flower to another; but when once the plant took to producing honey, the
insects largely gave up their habit of plundering the pollen, and went
from blossom to blossom in search of the sweet nectar instead. As they
did so, they brushed the grains of pollen from the stamens of one
blossom against the pistil of the next, and so enabled the flowers to
set their seed more economically than before.

Simultaneously with this change from fertilisation by the wind to
fertilisation by insects, there came in another improvement in the
mechanism of flowers. Probably the primitive blossom consisted only of
stamens and pistil, with, at best, a single little scale or leaf as a
protection to each. But some of the five-rowed flowers now began to
change the five stamens of the outer row into petals; that is to say, to
produce broad, bright-coloured, and papery flower-rays in the place of
these external stamens. The reason why they did so was to attract the
insects by their brilliant hues; or, to put it more correctly, those
flowers which happened to display brilliant hues as a matter of fact
attracted the insects best, and so got fertilised oftener than their
neighbours. This tendency on the part of stamens to grow into petals is
always very marked, and by taking advantage of it gardeners are enabled
to produce what we call double flowers; that is to say, flowers in which
all the stamens have been thus broadened and flattened into ornamental
rays. Even amongst wild flowers, the white water-lily shows us every
gradation between fertile pollen-bearing true stamens and barren broad-
bladed petals. To put it shortly and dogmatically, petals are in every
case merely specialised stamens, which have given up their original
function of forming pollen, in order to adopt the function of attracting
insects.

[Illustration: images/i026.jpg]

Fig. 8.--Transition from stamen to petal in White Water-lily.

The five-rowed ancestors of the daisy found a decided advantage in thus
setting apart one outer row of stamens as coloured advertisements to
lure the insects to the honey, while they left the inner rows to do all
the real work of pollen-making. They very rapidly spread over the world,
and assumed very various forms in various places. But wherever they
went, they always preserved more or less trace of their quinary
arrangement; and to this day, if you pick almost any flower belonging to
the same great division of dicotyledons (the name is quite unimportant),
you will find that it has at least some trace of its original
arrangement in rows of five. The common stonecrop and its allies keep up
the arrangement best of any; for they have each, as a rule, five petals;
each petal has its separate bract, making a calyx or flower-cup of five
pieces or sepals; inside are one or two rows of five stamens each; and
in the centre, a pistil of five carpels. Such complete and original
symmetry as this is not now common; but almost all the five-rowed
flowers retain the same general character in a somewhat less degree. The
buttercup, for example, has one outer row of five sepals, then five
petals, and then several crowded rows of stamens and carpels. And in the
petals at least the harmony is generally complete. There are five in the
dog-rose, in the violet, in the pea-blossom, in the pink, in the
geranium, and (speaking generally) in almost every plant that grows in
our gardens, our fields, or our woodlands, unless it belongs to the
other great division of trinary flowers, with all their organs in groups
of three. And now, if you will pull open one of the inner yellow florets
of your daisy, you will see that it has five stamens and five little
lobes to the bell-shaped corolla, to show its ancestry plainly on its
face, and 'to witness if I lie.'

[Illustration: images/i029.jpg]

Fig. 9.--Corolla of Primrose. 
Fig. 10.--Corolla of Harebell.

But the original bright-coloured ancestor of the daisy must have had
five separate petals, like the dog-rose or the apple-blossom at the
present day. How then did these petals grow together into a single bell-
shaped corolla, as we see them now in the finished daisy? Well, the
stages and the reasons are not difficult to guess. As flowers and
insects went on developing side by side, certain flowers learnt to adapt
themselves better and better to their special insects, while the insects
in return learnt to adapt themselves better and better to their special
flowers. As bees and butterflies got a longer proboscis with which to
dive after honey into the recesses of the blossoms, the blossoms on
their part got a deeper tube in which to hide their honey from all but
the proper insects. Sometimes this is done, as in the larkspur, the
violet, and the garden nasturtium, by putting the honey at the bottom of
a long spur or blind sac; and if you bite off the end of the sac in the
nasturtium you will find a very appreciable quantity of nectar stored up
in it. But most highly specialised flowers have hit upon a simpler plan,
which is to run all their petals together at the bottom into a tube, so
long that no useless insect can rob the honey without fertilising the
plant, and so arranged that the proboscis of the bee or butterfly can
rub against the stamens and pistil on the way down. In pinks and their
allies we see some rude approach to this mode of growth; for there each
petal has a long claw (as it is called), bearing the expanded part at
the end; and these claws when firmly pressed together by the calyx
practically form a tube in five pieces: but in the perfectly tubular
flowers, like the primrose, the arrangement is carried a great deal
further; for there we have the claws all grown into a single piece, with
the expanded petals forming a continuous fringe of five deeply cleft
lobes, representing the five original and separate pieces of the
pinks.[2] Now, in the primrose, again, we still find the five petals
quite distinct at the edge, though their lower portion has grown
together into a regular tube; but in the harebell or the Canterbury bell
we see that the whole blossom has become bell-shaped, and that the five
originally separate petals are only indicated by five slightly
projecting points or lobes which give the tubular corolla its vandyked
margin. And if you look at the little central florets of the daisy or
the sunflower, you will observe that they too exactly resemble the
Canterbury bell in this particular. Hence we can see that their
ancestors, after passing through stages more or less analogous to those
of the pinks and the primroses, at last reached a completely united and
tubular or campanulate form, like that of the heath or the Canterbury
bell.

[Illustration: images/i031.jpg]

Fig. 11.

Section of floret of Daisy.

There is one minor point, however, in the development of the daisy which
I only notice because I am so afraid of that terrible person, the
microscopic critic. This very learned and tedious being goes about the
world proclaiming to everybody that you don't know something because you
don't happen to mention it; and for fear of him one is often obliged to
trouble one's readers with petty matters of detail which really make no
difference at all except to such Smelfunguses in person. Being
themselves accustomed to weary us with the whole flood of their own
unspeakable erudition, every time they open their mouths, they imagine
that everybody else must be ignorant of anything which he doesn't
expressly state; as though you might never talk of a railway journey
without giving at full the theory of kinetic energy as applied to the
coal in the furnace. For their sake, then, I must add that, when the
daisy's ancestors had reached a level of development equivalent to that
of the heath and the Canterbury bell, they differed in one respect from
them just as the primrose still does. In the heath and the harebell, the
stamens remain quite separate from the tube formed by the petals; but in
the primrose and the daisy the stalks of the stamens (filaments, the
technical botanists call them) have coalesced with the petals, so that
the pollen seems to hang out in little bags from the walls of the tube
itself. This is a further advance in the direction of specialised
arrangements for insect-fertilisation; and it shows very simply the sort
of cross-connections which we often get among plants or animals. For
while the daisy is more like the Canterbury bell in the shape of its
corolla, it is more like the primrose in the arrangement of its stamens.
Or, to put it more plainly, while the Canterbury bell has hit upon one
mode of adaptation in the form of its tube, and while the primrose has
hit upon another mode in the insertion of its stamens, the daisy has hit
upon both together, and has combined them in a single flower. And now,
my dear Smelfungus, having given way to your prejudices upon this
matter, allow me to assure you that nothing will induce me to enter into
the further and wholly immaterial difference between hypogynous and
epigynous corollas. For every one but you, the very names, I am sure,
will be quite sufficient apology for my reticence. These, in fact, are
subjects which, like the 'old familiar Decline and Fall off the Rooshian
Empire,' had better be discussed 'in the absence of Mrs. Boffin.'

When the ancestors of the daisy had reached the stage of united tubular
blossoms, like the harebell, with stamens fastened to the inside wall of
the tube, like the primrose, they must, on the whole, have resembled in
shape the flowers of the common wild white comfrey, more nearly than any
other familiar English plant. The next step was to crowd a lot of these
bell-shaped blossoms together into a compact head. If you compare a
cowslip with a primrose, you can easily understand how this is done.
According to many of our modern botanists, cowslips and primroses are
only slightly divergent varieties of a single species; and in any case
they are very closely related to one another. But in the primrose the
separate blossoms spring each on a long stalk of its own from near the
root; while in the cowslip, the common stem from which they all spring
is raised high above the ground, and the minor flower-stalks are much
shortened. Thus, instead of a bunch of distinct flowers, you get a loose
head of crowded flowers. Increase their number, shorten their stalks a
little more, and pack them closely side by side, and you would have a
compound or composite flower like the daisy. In fact, we often find in
nature almost every intermediate stage: for instance, among the pea
tribe we have all but solitary flowers in the peas and beans, long
clusters in the laburnum and wistaria, and compact heads in the clovers.
The daisies and other composites, it is true, carry this crowding of
flowers somewhat further than almost any other plants; but still even
here you can trace a gradual progress, some approach to their habit
being made by allied families elsewhere; while some composites, on the
other hand, have stopped short of the pitch of development attained by
most of their race. Thus, certain campanulas have their flowers packed
tightly together into a head, which looks at first sight a single
blossom, just as deceptively as the daisy does; and a still nearer
relative, the scabious, even more strikingly resembles the composite
form. So that the daisies and their allies have really only carried out
one step further a system of crowding which had been already begun by
many other plants.

[Illustration: images/i034.jpg]

Fig. 12.--Section of head of Daisy.

If you look closely at the daisy, you will see in what this crowding
consists. The common flower-stalk is flattened out at the end into a
regular disk, and on this disk all the florets are seated with no
appreciable separate flower-stalks of their own. Outside them a double
row of leaves is arranged, exactly like the calyx in single flowers, and
serving the same protective purpose--to preserve the florets from the
incursions of unfriendly insects; while inside, the little individual
blossoms have almost lost their own calyxes which are scarcely
represented by a few tiny protuberances upon the seed-like fruit. In the
daisy, indeed, we may say that the true calyx has been dwarfed away to
nothing; but in the dandelion and many other composites a new use has
been found for it; it has been turned into those light feathery hairs
which children call 'the clock,' and which aid the dispersion of the
seeds by wafting them about before the wind.

Now, what has made the daisy and the other composites grow so small and
thick-set? Probably the need for attracting insects. By thus combining
their mass of bloom they are enabled to make a great show in the world,
and to secure the fertilisation of a great many flowers at once by each
insect which visits the head. For each floret has its own little store
of honey, its own stamens, and its own pistil containing an embryo
fruit; and when a bee lights upon a daisy head, he turns round and
round, extracting all he can get from every tiny tube, and so
fertilising the whole number of florets at a single time. The result at
least proves that the principle is a good one; for few flowers get so
universally fertilised, or set their seed so regularly, as the
composites. Though they must have reached their present very high state
of evolution at a comparatively recent period, they have spread already
over the whole world; and they are far more numerous, both in
individuals, in species, and in genera, than any other family of
flowering plants. In fact, they are undoubtedly the dominant tribe of
the whole vegetable kingdom. When I say that in Britain alone they
number no less than 120 species, including such common and universal
weeds as the daisy, dandelion, thistles, groundsel, camomile, milfoil,
hawkweed, and burdock, it will be clear that nine out of every ten
ordinary wayside blossoms which we see on any country walk are members
of this highly evolved, ubiquitous, and extremely successful family.

Still, we are far from having finished the pedigree of the daisy. We
have traced its general genealogy down as far as the common composite
stock: we have now to trace its special derivation from the early common
composite type to the distinctive daisy form. Clearly one great point in
the daisy's history is yet untouched upon; and that is the nature and
meaning of the white rays. We know that the inner yellow florets are (as
it were) dwarfed and specialised golden harebells; but we do not yet
know what is the origin of these long outer streamers, which look so
wholly unlike the tiny and regular central bells.

In solving this problem, the other composites will help us not a little;
for we must always seek in the simpler for the interpretation of the
more complex; and the daisy, instead of being the simplest, is one of
the most developed representatives of the composite pattern. If you turn
to that tall, rank-looking weed growing yonder, under cover of the
hedge, you will get a good surviving example of the earliest form of
composite. The weed is a eupatory--'hemp agrimony' the country people
call it--and it has small heads, each containing a few tubular purple
florets, all exactly the same size and shape, and all much more loosely
gathered together than in the daisy or the dandelion. The eupatory is
interesting as preserving for us one of the first stages in the ancestry
of the higher composites, after they had attained to their distinctive
family characteristics. Once more, I don't wish you to understand that
the daisies are descended from the eupatory: all I mean is, that their
ancestors must once have passed through an analogous stage; and that the
eupatory has never got beyond it, while the daisies have gone on still
further differentiating and adapting themselves till they reached their
present peculiar form. Now, if you compare this daisy with the head of
eupatory, you will see that they differ in two particulars--the daisy
has outer rays, while the eupatory has none; and the inner daisy florets
are yellow, while the eupatory florets are purple. The latter difference
is one into which we cannot enter now: it must suffice to say that when
the daisy's ancestors were in the eupatory stage of development they had
apparently all their florets yellow. This is likely, because almost all
the modern composites of every sort have yellow central florets, and
most of them have yellow rays as well. It is only a few kinds that have
red or purple central florets; and, as we shall soon see, only a few
also that have white or pink outer rays.

What, then, made the daisy's ancestors produce a row of external florets
so different in shape and colour from the internal ones? The answer is
exactly analogous to that which I have already given for the origin of
petals themselves. Compare the eupatory with the daisy once more, and
you will see that the one is comparatively inconspicuous, while the
other is very noticeable and bright-coloured. The row of green bracts
almost hides the blossoms of the eupatory; but the large white rays make
a bold and effective advertisement for the daisy. Certain composites, in
fact, have just repeated the same device by which the earliest petal-
bearing flowers sought to attract the notice of insects. Those early
flowers, as we saw, set apart one outer row of stamens as bright-
coloured petals; these later compound flower-heads have set apart one
outer row of florets as bright-coloured rays. If you examine the rays
closely, you will see that each of them is a separate little flower,
with the stamens suppressed, and with the bell-shaped corolla flattened
out into a long and narrow ribbon. Even these very abnormal corollas,
however, still retain a last trace of the five original distinct petals;
for their edge is slightly notched with five extremely minute lobes,
often nearly obliterated, but sometimes quite marked, and almost always
more or less noticeable on a careful examination. A daisy thus consists
of a whole head of tiny tubular bells, the inner ones normal and
regular, with corolla, stamens, and pistil, and the outer ones flattened
or ligulate, with the stamens wanting, and the entire floret simply
devoted to increasing the attractiveness of the compound mass. Pull off
the rays, and you will see at once what an inconspicuous flower the
daisy would be without them.

Last of all, the question arises, Why are the outer florets or rays pink
and white, while the inner florets or bells are golden yellow? When we
have solved that solitary remaining problem, we shall have settled the
chief points in the daisy's pedigree. Clearly, when the rays were first
produced, they must have been yellow like the central florets. The mere
flattening and lengthening of the corolla would not in itself tend to
alter the colour. And as a matter of fact, the vast mass of those
composites which have progressed to the stage of having rays--which have
got these two separate forms of flowers, for show and for use
respectively--have the rays of the same colour as the central bells,
that is to say, generally yellow. Of this stage the sunflower is a
familiar and very striking representative. It has bright golden central
florets, and large expanded rays of the same colour. To anybody who
wants to study the structure of the daisy without a microscope, the
sunflower is quite as valuable and indispensable as it is to our most
advanced æsthetic school in painting and decoration. Moreover, it shows
us admirably this intermediate stage, when the compound flower-head has
acquired a distinct row of outer attractive florets, adding wealth and
expansiveness to its display of colour, but when it has not yet
attempted any specialisation of hue in these purely ornamental organs.
The daisy, however, together with the camomile, the ox-eye daisy, and
many other similar composites, has carried the process one step further.
It has coloured its rays white, and has even begun to tinge them with
pink. This makes these highest of all composites the most successful
plants in the whole world. If one considers that daisies begin to bloom
on January 1, and go on flowering till December 31; that they occur in
almost every field far more abundantly than any other blossom; and that
each one of them is not a single flower, but a whole head of flowers--it
will be quite clear that they are much more numerous than any rival
species. And when we add to them the other very common white-rayed
composites, such as the camomiles, many of which abound almost as freely
in their own haunts and at their proper season, it is obvious that this
highly evolved composite type is the dominant plant race of the old
world at least. In the new world, their place is taken by a somewhat
more developed type still, that of the Michaelmas daisies, which have
their rays even more ornamental than our own, and brightly coloured with
mauve or lilac pigment. All the world over, however, in and out of the
tropics, the commonest, most numerous, and most successful of plants are
ray-bearing composites of one kind or another, like the daisies, with
the rays differing in colour from the central florets.

Finally, it may, perhaps, at first hearing, sound absurd to say that the
daisy group, including these other composites with tinted rays, forms
the very head and crown of the vegetable creation, as man does in the
animal creation: and yet it is none the less true. We are so accustomed
to look upon a daisy as a humble, commonplace, almost insignificant
little flower, that it seems queer to hear it described as a higher type
of plant life than the tall pine-tree or the spreading oak. But, as a
matter of fact, the pine is a very low type indeed, as is also the giant
tree of California, both of them belonging to the earliest and simplest
surviving family of flowering plants, the conifers, which are no better,
comparatively speaking, among plants, than the monstrous saurians and
fish-like reptiles of the secondary age were among animals. If size were
any criterion of relative development, then the whale would take
precedence of all other mammals, and man would rank somewhere below the
gorilla and the grizzly bear. But if we take complexity and perfection
in the adaptation of the organism to its surroundings as our gauge of
comparative evolution, then the daisies must rank in the very first line
of plant economy. For if we follow down their pedigree in the inverse
order, we shall see that, inasmuch as they have coloured rays, they are
superior to all their yellow-rayed allies (for example, the sunflower);
and inasmuch as these have rays, they are superior to all rayless
composites (for example, the eupatory); and inasmuch as composites
generally have clustered heads, they are superior to all other flowers
with separate tubular corollas (for example, the heathers); while all
these, again, are superior to those with separate petals (for example,
the roses); and all petalled flowers are superior to all petalless kinds
(for example, the pines and oaks). Thus, from the strict biological
point of view, it becomes quite clear that the daisies, asters,
chrysanthemums, and other rayed composites with coloured outer florets,
really stand to other plants in the same relation as man stands towards
other animals. That is what gives such a special and exceptional
interest to the daisy's pedigree.

* * *

## II.

### _THE ROMANCE OF A WAYSIDE WEED._

[Illustration: images/i045.jpg]

Fig. 13.--Hairy Wood-spurge (Euphorbia pilosa).

You will not find many pleasanter or breezier walks in England than this
open stretch of Claverton Down: certainly you will find very few with
more varied interest of every conceivable sort for every cultivated
mind. The air is fresh and laden from the brine of the Atlantic and the
Gulf Stream; the clear wind is blowing straight from seaward, not keen
and dry from the Eastern plains, but soft and pure from a thousand
leagues of uninterrupted ocean; and the view over the broken dale of
Avon, where it cuts its way in a veritable gorge through the high
barrier of the Bath oolite, stretches for miles over one of the
loveliest and greenest valleys in all our lovely green England. More
than that--the whole history of Britain is visibly unfolded before my
very eyes. That bald roundish hill to the right, with its smooth summit
artificially levelled, and its sides planed down into a long glacis, is
Little Solisbury; and Little Solisbury, as its name clearly shows, is
the very oldest Bath of all. For it is the bury or hill-fort of Solis,
the ancient fortified town of the Keltic and Euskarian natives; and
when, long ages afterwards, the Romans planted their station in the
valley below, they naturally called the hot springs which they found
there by the name of Aquæ Solis; and equally naturally misinterpreted
the second word (really a native term, Sulis) as the genitive of Sol,
and accordingly dedicated their great temple on the spot to Apollo.
Those straight white lines and green-grown ridges on the flanks of
Banagh Down and the eastern heights are the vestiges of the old Roman
causeways--the Fosse and its branches--now totally disused or else
degraded into modern cart-roads; and the Institution Buildings in the
valley below cover or contain all the remaining memorials of the stately
Roman town. Back of me again, on Hampton Down, stand the earthworks of
Caer Badon, the later British village, planted there when fear of the
heathen West Saxon invaders had driven back the Christian Welshman to
the hills which he had deserted for the fruitful valley during the
security of the Pax Romana; and this long mound, on whose summit I am
standing to catch the view, actually forms part of Wansdyke, the great
boundary barrier behind which the Welshmen of the Somersetshire
principality entrenched themselves, after the pagan English pirates had
taken possession of the Avon dale and of Bath itself. The decisive
battle which settled the fate of the city was fought at Dyrham Park,
among those blue downs on the northern horizon; and the tiny village of
Englishcombe, nestling below the solitary beacon of High Barrow Hill on
my left, marks in its very name the furthest westward extension of the
Teutonic settlers towards the ever-unconquered recesses of Mendip. As to
later associations, they are too endless for review. In the foreground
lies the town, and from its midst towers the abbey, the last flickering
effort of English architecture before the Reformation choked out its
life for ever; a tall and stately but very cold specimen of good late
perpendicular work. It rises above the ancient temple of Minerva, and
covers fragments of the older minsters--that which Osric, king of the
Worcester men, gave to a nunnery in 671; that which Offa of Mercia
raised in 775; that where Eadgar, first king of all England, was crowned
in 973: and that which the Angevin John of Tours erected in 1160. There
to the right is Lansdown, where the Parliament's men under Waller all
but wiped out the stout Cornishmen who 'stood up for their king' under
Sir Bevil Grenville in a fruitless victory; and the big tower on the top
is Beckford's Folly, built in a fit of Oriental recklessness by 'Vathek'
Beckford, and now the landmark of the cemetery which spreads over his
vanished domain. In the combe to the left, again, that huge pseudo-
classical manor-house is Prior Park, the vast rambling home of Ralph
Allen; and Ralph Allen was the original of Squire Allworthy, whose
grounds, as minutely described in 'Tom Jones,' are here actually
realised. But if I went on talking all day I should never have finished;
for the history of the Bath valley, as seen from Claverton Down, is, as
I said before, the history of all England, visibly epitomised in
tangible realities before one's very eyes.

However, I have not come out to-day to hunt for old relics among the
works of Caer Badon, or to trace the curious bends and angles of
Wansdyke. A far older and stranger chapter of our history than any of
these is unfolded by the little wayside weed which I have here in my
botanical case; and it was to find this very commonplace and
uninteresting-looking plant that I have come out this morning. For the
weed is the hairy wood-spurge, and Claverton Down is the only place in
Great Britain where that particular kind of spurge still lingers on. I
have got my British Flora safe here in my satchel; and now I am going to
sit down on the slope of Wansdyke and make quite sure that my plant
really tallies exactly with Dr. Bentham's description; for if it
actually does, then I shall have the pleasure of knowing that I hold in
my hand one of the few genuine links which yet unite us with a very
distant past--a past compared with which the days when Wansdyke was
built, or even when Little Solisbury was fortified, seem comparatively
recent. If this is in fact the hairy wood-spurge,[3] it and its
ancestors have been growing here on Claverton Down ever since the end of
the last glacial epoch; and it is a relic of the flora which once
bloomed among the lowlands that connected England and Ireland with
Brittany, Spain, and the Pyrenees. It dates back, in short, to the time
when Britain was still an integral part of the European continent.

A few minutes' examination with my pocket-lens is quite enough to assure
me that the flower I have picked is truly the wood-spurge of which I am
in search. It is a queer, insignificant little plant, with funny cup-
like green flowers, and odd jelly-bag glands, very much like most other
English spurges; but I see at once on a closer examination that it has
all the distinguishing marks of the hairy species--the woolly underside
to the leaves, the dotted seed-capsules, the loose umbels of blossom,
and the long branched rays supporting the straggling flower-heads. I
regard it, therefore, as a decided find; for the lane that bounds the
Prior Park estate, and this bit of woodland on the summit of Claverton
Down, are the only spots in England where this particular plant is now
found. But that is not all. In itself, the fact of its rarity would not
be enough to arouse any special interest; for there are many other wild
flowers found in only one spot in Britain--sometimes garden kinds
escaped from cultivation in a suitable climate, sometimes American
straylings, and sometimes high Alpine species requiring a particular
granite, basalt, or limestone soil--a soil perhaps to be met with in our
islands only on one or two scattered Welsh or Scottish hills of the
requisite height. The case of the hairy spurge, however, is very
different from any of these. It is a southern European and Western
Asiatic plant, and it spreads along the Mediterranean basin from the
Caucasus to the Pyrenees; but it nowhere comes any nearer to Britain
than the valley of the Loire. This is what gives it such a special
interest in my eyes. It is not found in Brittany, it is not found in
Normandy, it is not found on the opposite coast of Picardy, it is not
found in Kent or Essex; but it suddenly reappears here, out of all
reckoning, on Claverton Down.

If the case of the wood-spurge were a solitary one, it would be easy
enough to give a ready explanation. The neighbourhood of Bath is known
to be one of the warmest spots in England, having, in fact, its own hot-
water supply always laid on. This is a plant of warm countries. A bird,
let us say, once brought over a single seed, clinging to its feet or
feathers; an exotic flower, imported for the shrubberies of Prior Park,
was packed in earth containing young spurges; a sailor introduced it by
some chance; a botanist sowed it here for an experiment. Nay, perhaps a
Roman settler at Aquæ Solis brought it over with the plants for his
Italian garden. In such or the like casual manner it got a footing on
Claverton Down; and, as the climate suited it, it has gone on
flourishing ever since. Here, I say, would be an easy explanation if the
case of the hairy spurge were a solitary one; but, as a matter of fact,
there are hundreds of cases exactly like it. It is quite a common
occurrence to find a plant extend all through Europe from the Caucasus
to the Pyrenees, then stop suddenly short, and turn up again once more
incontinently in Devon, Cornwall, Kerry, and Connemara. This is such a
curious fact that it really seems to call for some adequate explanation.

[Illustration: images/i052.jpg]

Fig. 14.--Flowers of common Monkshood.

Let me begin by noting a few of the most striking instances. There is in
the Bristol Channel a solitary rocky islet known by the old Scandinavian
title of the Steep Holme--a name given to it, no doubt, by the wickings
of the ninth century, who made it their headquarters for plundering the
chapmen and slave-mongers of wealthy Brycgstow. Now the rocky clefts of
the Steep Holme are still crimson in May and June with the brilliant red
blossoms of the wild pæony, a flower which does not elsewhere appear
nearer to England than the Pyrenees. Not far from Axminster in Devon,
again, there is a warm sheltered nook in which nestles the little
village of Kilmington. Well, Kilmington Common is a place famous to
botanists, because it is the one single station in Britain for a small
purplish lobelia, which ranges elsewhere only from Andalusia to central
France. Dozens of like cases may be noted in the south-western peninsula
of England and the similarly situated corner of Wales about
Pembrokeshire. Thus, to lump a long list briefly, the common blue
monkshood is found wild in South Wales and the Cornish district only;
the yellow draba is confined to old walls about Pennard Castle, near
Swansea; the spotted rock-cistus occurs only in the Channel Islands and
at Holyhead; the white rock-cistus is peculiar in Britain to Brent Downs
in Somerset, together with Torquay and Babbicombe in Devon; the Cheddar
pink, a volcanic plant of southern Europe, clings to the crannies of the
Cheddar cliffs near Wells, and to no other crag in England; the soapwort
is wild only in Cornwall and Devon; the flax-leaved St. John's wort
grows nowhere but at Cape Cornwall and on the banks of the Teign; the
crimson clover and Boccone's clover are entirely restricted to the
peninsula of the Lizard; so also is the upright clover, save that it is
likewise found in the Channel Islands; the sand bird's foot remains only
at Scilly; the Bithynian vetch extends through Europe as far north as
Bordeaux, and then disappears again till after a sudden leap it is
gathered once more in Devon and Cornwall; the white sedum occurs in the
Malvern Hills and in Somersetshire; and the narrow buplever flowers only
at Torquay and in Jersey and Guernsey. In almost all, if not in all,
these cases the plant is a southern one, which extends usually from the
Caspian to Spain, is perhaps found as far north as the Gironde or even
the Loire, and then disappears again till it turns up suddenly in some
exceptionally sheltered nook of Devon, Cornwall, or South Wales. This is
a phenomenon which cannot surely be due to chance alone. Indeed, I might
greatly increase the list, but I refrain only because I am afraid of
being wearisome.

When we turn to the similarly placed south-western corner of Ireland,
the peculiarities we meet are even more remarkable. I shall never forget
my surprise when once, after my first visit to Nice and Mentone, I began
describing the beautiful Provençal flowers to an Irish botanist, and was
quietly answered, 'Ah, yes; we have them all at Killarney.' But it is
really true none the less. The thick-leaved sedum, after skipping all
England and Wales, shows itself suddenly in the Cove of Cork. The pretty
Mediterranean heath, which every winterer at Pau has gathered by
handfuls on the hills about Eaux Chaudes or Cauterets, jumps at a bound
to the coast of Kerry. The arbutus, with its clustering white blossoms
and beautiful red berries, is similarly found in Provence and again at
Glengariff. London Pride grows wild in Portugal, western Spain, and the
higher Pyrenees, and reappears in south-western Ireland. Another pretty
little saxifrage jumps in like manner from the Asturias to Killarney.
St. Dabeoc's heath has the same range. The spiked orchid takes a great
bound from Bordeaux to a single station in County Galway. To sum it up
shortly, 'Crete, Auvergne, the Pyrenees, S.-W. Ireland,' is a common
technical description of the distribution of many beautiful south
European plants.

[Illustration: images/i055.jpg]

Fig. 15.--Flower and fruit of Arbutus.

Now, these peculiarities of distribution lead me up pretty surely to the
romance of the hairy wood-spurge. They show that it did not get here by
accident. Like the elephant-headed god of the Mexicans, like the debased
traces of Buddhism in the Aztec religion, they raise an immediate
curiosity as to their origin. What we may call the natural range of
British plants is of this sort: they have entered the country from the
Continent, _viâ_ Kent, Sussex, East Anglia, or Scotland; and they fall
for the most part under three great divisions. The first division
consists of central European plants, which seem as if they had come in
from the east: and of these a few get no farther than the eastern
counties; a great many spread over the whole country; and the remainder
have reached to the west and to Ireland. The second division is that of
the Scandinavian plants, which seem as if they had come in from the
north; and of these a few stop short in Shetland, Orkney, or the
Highlands; others get as far as the midland counties; and a good many
straggle on into Kent or Cornwall. The third division comprises the
mountain plants, which have come in from various quarters, and which
grow wherever the elevation and the mountain air suit their
constitutions. But my wood-spurge agrees with none of these, and it
clearly belongs to another southern class, which cannot have entered
Britain by any of the customary routes _viâ_ Dover, Harwich, or
Southampton. It seems to have taken a route of its own, and to have
attacked England by way of Bristol and Bordeaux. Otherwise, we should
find it and the other peculiar west-country species in the warmer parts
of Kent, Surrey, and the Isle of Wight, which, as a matter of fact, we
never do. If climate were the only agent at work, Ventnor certainly has
as good claims as any place in England.

Perhaps it seems a useless question to inquire how they came there at
all. 'Were they not always there?' somebody may ask me. And the answer
is, No, undoubtedly not. You might as well explain the presence of an
English-speaking colony on Pitcairn Island by the hypothesis that
Englishmen were originally created in two separate centres--Great
Britain and the South Pacific. Only some 80,000 years since--a mere
single swing of the cosmical pendulum--every inch of Great Britain and
Ireland, save only an insignificant southern fringe, was wholly covered
by the ice of the last glacial period. We know the date with
mathematical certainty, because the astronomical conditions upon which
glacial periods have been shown almost beyond doubt to depend, began
200,000 years ago, and ended 80,000 years ago. During the interval
between those two dates, the condition of each hemisphere alternated
between long cold periods and long hot periods, of some 10,500 years
each. During the last cold spell, all England and Ireland were in the
condition of Greenland at the present day. The ice had planed every
living thing clean off the face of the country, and we may still trace
its scratches on the smooth granite bosses of Wales and Scotland, or
find its till and its moraines on the plains and valleys of East Anglia
and Derbyshire. Consequently the ancestors of every plant and every
animal now living in Britain must have come into it after the end of the
last long cold spell--that is to say, roughly speaking, some 80,000
years since.

Moreover, when Britain was repeopled after the great ice age, it must
have been united to the Continent somewhere, or else it could not
possibly possess the large number of European plants and animals which
it actually contains.[4] Had it then been an island, it might have had a
considerable population of ferns and small-seeded flowers, of birds and
winged insects, blown over to it from the shores of France or Holland;
it might even have had a fair sprinkling of snails and lizards, or a few
small quadrupeds, wafted across on logs of wood, or carried over
accidentally by various chances; but it would be quite impossible that
it should have all the species of large or middle-sized wild mammals
which we see now inhabiting it--the red deer, the fallow deer, the
otter, the badger, the fox, the hare, the rabbit, the weasel, the stoat,
the marten, the hedgehog, the wild cat, the mole, the shrew, the
squirrel, and the water-vole. Altogether, we have no less than forty
species of British mammals; while the bear, the wild boar, the beaver,
the reindeer, and the wolf have become extinct within the historical
period; and the wild white cattle even now survive sparingly in
Chillingham Park and a few other scattered places. Clearly, as none of
these animals or their ancestors can have been in Britain 80,000 years
ago, they must have come into Britain at some later date, across a wide
bridge of solid land. For Mr. Wallace has conclusively shown that
islands which have never formed part of a mainland never have any
terrestrial mammals at all; and that a very narrow strait is quite
sufficient to prevent the passage of mammals from one island to another.
The sound which divides the Indo-Malayan region from the Australian
region is hardly wider than that which separates England from France;
yet not one single Australian mammal has ever reached the Indo-Malayan
region, and not one single Indian mammal has ever reached Australia. The
kangaroos, wombats, phalangers, and cassowaries of the one district are
quite distinct in type from the elephants, tapirs, tigers, deer, and
monkeys of the other. So that our numerous existing English fauna must
certainly have crossed over on dry land.

We may take it for granted, then, that the mass of British plants came
in, from the east and south-east, immediately after the ice of the
glacial epoch had passed away. For the ice had driven man and beast,
herb and tree, southward before it; and even if there was a little
fringe of what is now Southern Britain not wholly glaciated, yet its
condition must have been like that of the little habitable fringe in
Greenland, and its plants and animals (if any) must have been of
thoroughly Arctic types. But as the glaciers cleared away again, with
the return of the sun to the northern hemisphere after its long cold
cycle, the southern and eastern plants and animals must have followed
the retreating ice-sheet from year to year; till at last the species
which used to inhabit Kent and the Isle of Wight found their permanent
home in Lapland, and those which used to inhabit Greece and Italy found
their permanent home in Holland, Denmark, and Great Britain.

This sufficiently accounts for the presence in England and Scotland of
the central European and Scandinavian elements; but it does not account
for the presence of my hairy spurge and of all the other south-western
species, belonging to the Pyrenean and Italian region. Clearly, the
ordinary plants of Eastern England are plants which once spread
uninterruptedly from Warwickshire to Central Europe, when the belt of
land over the German Ocean was still entire; and clearly, too, the
ordinary plants of the North and of Scotland are plants which once
spread uninterruptedly from Yorkshire to Scandinavia, during the same
period; while both classes have been afterwards isolated in Britain by
the gradual subsidence of the intervening land. But this still leaves
unanswered the question, Whence did we get the Pyrenean types?

Perhaps one might be disposed at first sight to fancy that they came
over separately, as we know a few American plants have really done.
There is the well-known Canadian canal weed, which was introduced by a
botanist into a tank near Cambridge in 1845, and rapidly spread over all
England; there are a few orchids and other wild flowers whose seeds have
apparently been carried across the Atlantic on the feet of birds; and
there are some half-dozen escaped garden flowers, like the evening
primrose, which have established themselves easily among some rare warm
spots in our congenial climate. Possibly it might seem as though the
arbutus, the hairy spurge, the Mediterranean heath, and all the rest of
the southern species in South-Western England or Ireland had got across
to us in somewhat the same fragmentary fashion, and had succeeded in
effecting a foothold only in these warmer Cornish and Irish nooks. But
there are a great many reasons against believing this. In the first
place, we have the immense number to account for--at least ninety
species, all told; which is a prodigious item to set down to the chapter
of accidents. For the distance from Bordeaux to Kerry is really 700
miles, while the distance from Portugal to the Azores (which are peopled
with plants and animals in the most fragmentary manner) is only 900; and
we can hardly suppose that so large a number of southern plants could
permanently establish themselves (against the prevailing winds) in a
country already occupied by a flourishing native flora. But two more
fatal objections are these: First, our southern plants are only found in
the extreme south-west, and not in the warmest parts of the Isle of
Wight, of Kent, or of Hampshire. Even at Bournemouth and Ventnor we meet
with none of them. And secondly, they are all evidently dying out; they
represent an old flora which is no longer adapted to the country, not a
new flora pushing its way vigorously into regions occupied by less
congenial plants. Every year they are disappearing before our very eyes,
and many of them are from time to time now being expunged from our
floras. The Kilmington lobelia is getting rarer as every summer passes;
the wild asparagus, once common on the Lizard promontory, is now only to
be picked, at the imminent risk of life and limb, amongst the crannies
of a rocky islet at Kynance Cove; the purple viper's-bugloss has been
driven to the very extremity of Britain at Penzance; while the various
kinds of rock-cistus, the Steep Holme pæony, and the Cheddar pink linger
on each only in a single inaccessible spot in the south-western
peninsula of England. These are clear evidences that they form the last
stragglers of a vanquished flora, not the vigorous vanguard of a
victorious and aggressive race.

And now we are in a position fairly to settle the problem where the
hairy spurge and its fellows have come from, and how they got here.
People who recognise the fact that Britain was once joined to the
Continent are too apt to fancy that it was joined only by a sort of
narrow bridge between Dover and Calais. The aspect of the shore on
either side, the high bluffs of Shakespeare's Cliff and Cap Grisnez, the
geological continuity between the chalk and the other formations on the
two coasts, all forcibly suggest that France and England must once have
been joined there--as, indeed, they undoubtedly were. But we are all
inclined mentally to minimise the amount of connection; we stick in an
isthmus just sufficient to carry the South-Eastern Railway across to
Boulogne, and then we are fully satisfied with our new geography. In
reality, however, the old land connection was something far more
complete and universal than that. There is every reason to believe that,
at the close of the last glacial epoch, Great Britain and Ireland formed
a part of the Continent, not in the sense in which Scandinavia or
Denmark still does, but in the sense in which Bavaria and Switzerland
still do. The land of Europe then stretched out to seaward far beyond
Ireland, Spain, and the Faröe Islands; and Cork, Glasgow, and Liverpool
then stood further inland than Lyons, Munich, and Geneva stand at the
present day.

Walking one morning a few winters since--just after the most terrible
tempest of recent years--on the Parade at Hastings, I happened to notice
a curiously shaped flint among the shingle lately thrown up by the great
storm. The waves had beaten right over the sea-wall, and scattered a
litter of wrack and pebbles along the whole roadway. I stooped down and
picked up the odd-looking fragment: to my surprise, I found it was a
palæolithic implement, a rudely chipped flint knife of the older stone
age, the relic of a race compared with whom even the builders of
Wansdyke here were men of yesterday. This rude flake was fashioned by
the naked black-fellows who hunted the rhinoceros and the mammoth in the
English valleys, before ever the great ice age itself had spread its
glaciers over the length and breadth of the land, a couple of hundred
thousand years since. Its outer surface was dulled and whitened by age,
as is always the case with these primæval flint weapons; but its edge
was still sharp and keen, though crusted in places with a hard film of
mineral deposit, and also blunted here and there by use in cutting clubs
and reindeer bones for its savage possessor. But there were no traces of
rolling as in water-worn pebbles: the knife was freshly disinterred. It
was clear that the storm had just unearthed it from beneath the
submerged forest which belts all the coast from Beachy Head to
Dungeness. For the forest is a post-glacial deposit; and it once formed
part of this great connecting land, now buried beneath the Atlantic, the
English Channel, and the German Ocean. The trees which composed it still
stand as upright stumps, firmly bedded in a layer of tenacious clay; and
strewn beneath them lie prostrate boles, in the very place where the
wind threw them down some fifty or sixty thousand years ago. In the
public garden at Hastings, one of these huge balks, dug up on the St.
Leonard's beach, has been fixed as a curiosity; and, though its outer
layer is charred and blackened by the water, the inner wood is still as
sound and as firm as on the day it fell. We have to deal here with a
time which is marvellously ancient indeed when measured by our ordinary
human and historical chronology, but which is quite modern when judged
by the vast timepiece of cosmical and geological cycles.

All round the coast of England you will find endless traces of these
submerged forests, especially wherever the land shelves off slowly to
seaward. That most lively of mediæval travellers, Giraldus Cambrensis
(whose amusing and somewhat slangy diary would be much more read, I am
sure, if people did not incongruously mistake him for a dry chronicler
of the monastic sort), gives a full and really scientific account of one
which he came across in the course of his Welsh peregrinations; and ever
since his time the submerged forests have been noted in spot after spot
in every part of Southern Britain. Beginning in the great bight between
Wales and Scotland, they continue round the coast at Holyhead; turn up
again in Cardigan Bay; fringe the whole Bristol Channel; fill in the
bottom of the fiords at Falmouth, Dartmouth, Torquay, and Exmouth; trend
round the Isle of Wight, Selsea, and Pevensey Bay; appear sparingly off
the Essex coast; and thence run up by Cromer and the Wash to Holderness
and Lindisfarne. They are everywhere newer than the glacial deposits,
and so they give us a fair ground for believing that a great general
subsidence of the land has taken place all round the shore of England at
a comparatively recent period--that is to say, since the close of the
last glacial epoch. How recent they are is well shown by the nature of
the remains themselves; for they often contain undecayed leaves, water-
logged hazelnuts, bits of small twigs, and other forestine rubbish of a
perfectly undecayed and modern-looking character. Some of the twigs even
break with a sharp crackling sound, like dry wood freshly taken from a
modern forest.

[Illustration: images/i068.jpg]

Fig. 16.--Sketch Map of Post-Glacial Britain.

The question now remains, If the land once thus extended farther out to
sea than at present, how far out did it extend? or, in other words, how
large a subsidence has taken place? Here we have an excellent hint for
our guidance in the fact that Ireland must have been united to England
since the glacial epoch, because we find in Ireland a large proportion
of the British plants and animals, including a considerable number of
land mammals. Now, how much must we raise the general land surface of
the British Isles in order to unite Ireland to Great Britain? Well, a
rise of less than one hundred fathoms would suffice to join the whole of
our islands throughout nearly all their length, leaving only two large
lakes in the very deepest parts of the sea, where the plummet marks a
depth of a hundred and fifty fathoms. One of these two large lakes would
lie between Galloway and Ulster, and the other would fill up the hollow
of the Minch between the Hebrides and the Isle of Skye. But the same
amount of elevation would also suffice to unite us to the Continent from
Denmark to Spain, as well as to push out our whole coast-line about
fifty miles to the westward of Cape Clear. Beyond that distance the sea-
bottom suddenly topples over from a general depth of a hundred fathoms
to a depth of a thousand fathoms or more; which clearly shows that this
line, curving round from Shetland to the Spanish shore of the Asturias,
must mark an old and long-continued prehistoric land-barrier. In other
words, the British Isles are situated on a comparatively shallow
submarine bank, which spreads north, south, and east of them, but ends
abruptly to the westward by a sudden drop of eight or nine hundred
fathoms. If you were now to raise this bank a hundred fathoms in height,
you would lift its whole area above the sea-level, save only in the two
hollows already noted; but if you went on raising it for several hundred
fathoms more, you would not materially alter the coast-line established
by your first elevation. So we can hardly doubt that the hundred-fathom
line really represents the old western boundary of Europe towards the
Atlantic, because it coincides so nearly in depth with the elevation
necessary to unite England and Ireland to one another, and to the
Continent.

Only one element of our problem now remains to be solved; and that is
the question--When did the subsidence take place which turned the dry
land all round Britain into the beds of the English Channel, the German
Ocean, and the Irish Sea? To this question I am deferentially inclined
to give a somewhat different answer from that of most of our
authorities. As a rule, it seems to be implied that the subsidence was a
single act, spread indeed over a considerable length of time, but
completed once for all, and never since renewed. It appears to me more
probable, however, that the subsidence has been going on more or less
ever since the age of the submerged forests, and that it still continues
in places over the same area. Mr. Wallace has already pointed out that
Ireland was probably separated from the mainland sooner than England,
because it has fewer native mammals and hardly any reptiles or
amphibians. The happy immunity from toads and serpents which is
generally attributed to the pious exertions of St. Patrick, may perhaps
rather be set down to the early isolation of Ireland from the mainland
shortly after the end of the great ice age, and before all the members
of the new European fauna had had time to spread equally over the more
outlying portions of the yet undivided continent. But there are other
indications of subsequent partial submergence elsewhere. Many facts lead
me to the belief that the Bristol Channel was still a plain through
which the Severn flowed quietly to the sea long after the final
insulation of Ireland and the Hebrides. Tourists driving from Barmouth
to Port Madoc have looked down from the picturesque escarpment of
Harlech Castle upon a narrow belt of plain between the mountains and the
sea, and have been told how the Lowland Hundred once stretched outward
from this point across Cardigan Bay as far as Sarn Badrig or St.
Patrick's Causeway, a rocky reef which whitens the Channel into a long
line of breakers in the middle distance. Welsh legends, immortalised by
Peacock's delicious satire, tell us how the Hundred was submerged by an
inundation; and the tradition as to this subsidence is almost certainly
correct. There is some ground for believing that the Isle of Wight was
still united at ebb tide to the mainland of Hampshire by a sandy
isthmus, when the Romans built their villas at Brading; and we know that
even as late as the days when Hengest and Horsa launched their mythical
long ships for the conquest of Kent, the Zuyder Zee was yet undoubtedly
an inland lake, separated from the German Ocean by a long belt of land
now almost entirely submerged, save in the solitary line of islands
which preserves the outline of its northern shore. Nay, even in our own
time, the southern part of Sweden is slowly sinking by inches beneath
the level of the Baltic. Hence I am strongly inclined to suspect that
the submergence of this western land was a work of time, and that no
particular date can be assigned to it as a whole.

Now, when a continuous belt of lowland stretched round from Spain to
Ireland and the Shetlands, we can easily understand that the warm type
of south European plants would run northward along its western shore as
far as the climatic conditions permitted. But the climate on all the
west coast of northern Europe is exceptionally mild and moist, through
the agency of the Gulf Stream and the warm westerly breezes which blow
across it. Hence it is not surprising that the Mediterranean heath, the
strawberry tree, the pæony, the hairy spurge, and all the other southern
plants which I have before scheduled, should have ranged all along the
Atlantic shore of Europe, past the Pyrenees and the Asturias, up the
bend a hundred and fifty miles west of the Land's End, and so onward to
Kerry and Connemara. Dr. James Geikie has recently shown good reasons
for believing that the last glacial epoch was immediately succeeded by a
short spell--say a thousand years or so--of very sunny and genial
conditions in northern Europe; and while these favourable conditions
lasted we can readily understand that the southern flora may even have
extended along the sheltered belt beneath the mountain-ranges of Ireland
and Scotland as far northward as Bute and Arran, where some few of its
hardier representatives are actually still preserved. Meanwhile, the
eastern level slope of what is now England, together with Holland and
the intervening land which then filled up the basin of the German Ocean,
must have had an inland continental climate, exposed to the full rigour
of the north-east winds, and unmitigated by the warmth and moisture now
diffused over it by the sea and its currents. In short, the condition of
that great tableland must have been much like the condition of Central
Russia at the present day, aggravated perhaps by an extra elevation to
some hundreds of feet above its existing level. Here, then, the flora
must have been of the central European and Scandinavian type; while west
of the great central range of England, the trees and flowers must in the
main have resembled those which we now find among the nooks of the
Apennines and the Genoese Riviera.

By-and-by, however, the earth's crust began to sink in western Europe,
as it is sinking now in Scania and the bed of the southern Baltic.
Slowly the great Atlantic plain disappeared below the waters, leaving
only the mountain-tops and higher plateaus as islands above the sea-
level. First the two lateral valleys of the old lake-system were
flooded, cutting off Ireland and the western Hebrides as two large and
compact islands, considerably bigger than they now remain at the present
day. Then, doubtless, the North Sea and the Channel were overflowed,
leaving only a narrow neck of chalk downs as a connecting link between
Kent and Picardy, which the waves gradually beat down and at last
destroyed. The cliffs of Dover and Cap Blancnez, of Beachy Head and
Dieppe, now mark its limits. Still the Bristol Channel remained an open
valley, and Scilly was united to the Cornish peninsula. Next, Scilly and
the Channel Islands went; while the Hebrides and the western coast of
Scotland broke up into a number of separate islets, only the granite
crests of the higher mountain-ranges now overtopping the water in long
lines, while the lateral valleys became the straits which separate the
various members of the different archipelagos from their nearest
neighbours. Any one who has once yachted down the broken ridge of the
Outer Hebrides cannot fail to have noticed that they seem but the
summits of a vast sunken range, jagged and beaten at the outer edge by
the ceaseless dash of the Atlantic. Last of all, apparently, went
Anglesey, Wight, and the coastwise eyots, as well as the Bristol
Channel. On the protected eastern shore of Britain generally, the low
slopes have survived well enough, and patches of shingle and sand, like
the Dogger Bank, still mark the position of the higher sunken lands; but
on the west and north the open Atlantic has eaten away all but the most
sheltered plains, and cut its way at all exposed points into the heart
of the hills, giving rise to the magnificent cliff scenery of Cornwall,
Kerry, and the western Highlands. If you stand upon the shore of Coboe
Bay in Guernsey, and look at low tide across the vast floor of jagged
and water-fretted granite rocks which line its bottom, you will see with
what force the waves have wormed their way over all the lowland; and
they will only halt when they have planed down the whole of the island,
as they have already planed down the lesser land which once stretched
out to northward beyond the solitary pinnacles of the Casquets.

When all these changes had taken place, the stray members of the
southern flora in Cornwall, Devon, Kerry, and Connemara would find
themselves quite cut off from their fellows in the Mediterranean, the
Pyrenees, and the Asturias. For the water has eaten away almost all the
plain of the Bay of Biscay, save only a comparatively insignificant
angle between the Loire, the mountains of Auvergne, and the roots of the
Pyrenees; and it has left the high and bleak granite moorland of
Brittany jutting out alone into the western sea. But Brittany looks
northward, and is open only to the chilliest winds; while its fair share
of the Gulf Stream is diverted by currents due to the lay of the land in
Cornwall. Moreover, the great bight of Biscay distracts and upsets the
old run of the water, so that the whole shore of France from the Garonne
northward is really colder and less equable in temperature than Cornwall
and Kerry, or even than the average of our own western and southern
coast. The Vendée is a chilly marshland; Bretagne Bretonannte is a high
and wind-swept heath. On the other hand, our extreme south-western
peninsulas and islands are bathed on every side by the warm water of the
Gulf Stream, and so possess an unusually mild, damp, and equable
climate. Every one has heard of the semi-tropical vegetation of palms
and aloes which flourishes in the open air at Tresco Abbey in the Scilly
Isles. Here, then, we have exactly the conditions under which the
southern plants, though beaten back to the very base of the hills, might
still manage to keep up a precarious existence in a few scattered and
sheltered nooks. And that is exactly what they have done. Separated from
all the rest of their kind, exposed to occasional hard winters or heavy
frosts, and slowly dying out under our very eyes, they have yet left
here and there a few isolated descendants to tell the story of their
origin and their failure. Curiously enough, these little lingering
colonies of Mediterranean plants exist only on the southern and western
slopes, among the cliffs and combes and bays which face and overlook the
submerged lands whence their ancestors were driven by the advancing sea.
So oddly do they confine themselves to the islands and the most insular
peninsulas that their geographical distribution almost looks like a
preconcerted arrangement.

Thus we may observe once more that one little islet of the Bristol
Channel alone preserves the red pæony. Holyhead Island has half a dozen
rare species. The Jersey centaury, Pelisser's linaria, and several other
southern flowers have died out everywhere save in the Channel Islands.
Scilly shares with them in the sand bird's foot. The Irish Arran and
other Irish islands have many peculiar species; and a few southern types
even reach Bute and the western Highlands; for, as every one knows,
Rothesay has a climate almost as warm as Torquay. So, too, with the
peninsulas. The Lizard, with the most equable temperature on the English
coast, is a perfect mine of wealth to the botanist. It has three
peculiar southern clovers, and lots of other rarities. Penzance, at the
very horn of Cornwall, has five or six specialities. The position of
Kerry gives it a climate like that of Finisterre, with the appropriate
flora. Wild madder belongs only to a few headlands of Pembrokeshire, the
Damnonian peninsula, and the south-west of Ireland. Torquay, on the
promontory of Hope's Nose, shares a southern buplever with the Channel
Islands. Babbicombe has a species almost to itself. Corfe Castle, in the
so-called Isle of Purbeck in Dorset, divides a Spanish heather with
Cornwall and the West of Ireland. One kind of rest-harrow, after getting
up from the Pyrenees as far as the Channel Islands, then positively
takes a second spring to the Mull of Galloway. As to the number of
Mediterranean plants which are found in Britain only in Devon and
Cornwall, or in Kerry and Connemara, or in both, I spare you the recital
of them. Even the more inland and moorland types, which each survive on
one high common alone, answer to the same law; for they occur on the
warmest moors, in the neighbourhood of the sunniest south-western
slopes. Thus the Cheddar pink grows in a single basking hollow heated by
radiation from two great walls of limestone rock upon the western flanks
of Mendip; the purple lobelia loiters on a bright upland near the warm
valley of the Devonshire Axe; the white sedum struggles on upon the edge
of Malvern; and my hairy wood-spurge here battles hard for life on
Claverton Down, close to the steaming basin of the old Roman Thermæ at
Bath.

And so I end where I began. My sermon has led me far afield; but, like a
good preacher, I have come back to my text. I have only touched lightly
upon the simplest and least technical proofs; but when the whole
evidence is put together--as I do not pretend to put it together off-
hand, sitting here cross-legged on the edge of Wansdyke--there can be
very little reasonable doubt that this is something like the way in
which the hairy wood-spurge first found its way to the Prior Park Lane.
So I have gathered my little morsel tenderly and carefully, not injuring
the little plant more than I can help by my clumsiness; and I hope all
future botanisers will do the same, in order to aid in preserving and
handing down to after ages this interesting fragment of old English
history, kept green and vital for us all in the tiny blossom of a
wayside weed.

* * *

## III.

### _STRAWBERRIES._

[Illustration: images/i081.jpg]

Fig. 17.--The Wild Strawberry.

Side by side in our English hedgerows in early springtime there grow two
sister plants, almost exactly alike in foliage, flower, and all other
points except the fruit, but differing widely from one another in that
solitary, and to us essential, particular. One of these plants is the
wild strawberry, the other is the little three leaved, white potentilla.
It is not often that a parent species and its more developed offspring
survive together in the same district, but this is almost certainly the
case with these two small English wayside flowers. Indeed, the
similarity between them is so close that even the most unobservant
passers-by have been greatly struck with it; and the common native
English name of the white potentilla--'barren strawberry'--bears witness
to the striking character of the family likeness. Perhaps one ought
rather to go a step further, and to say that, while the most unobservant
have perceived the relationship, only the more observant have ever
discovered the distinctness of the two plants. Nothing is more ordinary
than to hear casual townsfolk exclaim that though there were lots of
strawberry blossoms a little while ago in such-and-such a spot, there
are no ripe strawberries to be seen now that the time has come for
picking the fruit. In such cases, careful examination will generally
show that the spot is really covered by white potentilla plants, whose
little starry flowers were easily mistaken by the world at large for
true strawberry blossom. Though there are some marked distinctive
features even in the flower, to which I shall presently recur, it is in
the fruit alone that the two plants really differ sufficiently to
attract the attention of an unbotanical eye. But here the difference is
one which touches humanity on a very keen point indeed, for the
strawberry blossom sets at last into a sweet and pulpy berry, while the
potentilla blossom sets only into a small head of dry and unpalatable
nutlets. How the edible fruit has developed from the inedible seeds is
the question which I propose briefly to investigate in the present
paper.

To get properly at the ancestry of the strawberry, we ought first to
begin with the potentillas at large, for a most important part of our
evidence consists in the fact that the white potentilla varies from the
central type of its race in nearly all the same particulars as the
strawberry plant. In other words, we have to show that the ancestors of
the strawberry had already acquired most of their existing peculiarities
while they were still white potentillas, and that they have only then
varied so far as to have added to that white potentilla type the one
extra peculiarity of a red and juicy berry. Our systematic botanists,
indeed, will tell us that while the one plant belongs to the genus
_Potentilla_, the other plant belongs to the totally distinct genus
_Fragaria_; and they imply, therefore, that the differences between the
real strawberry and the barren strawberry are far greater than the
differences between the barren strawberry and the other potentillas. I
hope in the sequel to show, however, that it would be far easier to
develop a strawberry out of a white potentilla than to develop a white
potentilla itself out of any one among its yellow allies; and therefore
that the systematic classification is a faulty one, and the popular
classification a correct stroke of half-unconscious scientific
intuition.

The potentillas are a group of very lowly and primitive roses, the
earliest and simplest surviving members of the great and world-wide rose
family. Our common English cinquefoil may be accepted as a good typical
instance of the whole group. Cinquefoil is a pretty tufted creeping
plant, whose small golden flowers, like yellow roses in miniature, star
the waste grass-plots by the sides of lanes and highways everywhere in
Britain during the summer and autumn months. Its leaves, as the very
name denotes, consist of five separate spreading leaflets, all springing
from a common point, and radiating round it as a centre like the fingers
of a hand. The flowers, as usual in most very simple and primitive
plants are bright golden yellow, and they closely resemble the equally
early blossoms of the buttercup, which similarly form the starting point
of another great and varied family. Originally, there is good reason for
believing, all flowers were of this same bright golden yellow hue; and
those of them that have since progressed to other colours, under stress
of special insect selection, have passed through regular gradations of
white, pink, red, crimson, purple, and finally blue. Some flowers still
remain at the ancestral yellow stage; others have got on as far as white
or pink; yet others have attained the stage of crimson or purple; and a
very few, the most advanced of all, have even reached the culminating
glory of deep blue.

We have several other yellow potentillas in England besides the
cinquefoil, and some of these have varied a good deal in foliage or
other points from the central form. Nearest of all to it stands the
small tormentil, so frequent upon heaths or other moors and uplands; for
the main distinction between them lies in the fact that the cinquefoil
has usually five large petals, while the tormentil has usually only
four. This difference, however, is by no means always constant, for on
the one hand it is easy to find stray flowers of cinquefoil with only
four petals, while on the other hand the first flower on each stalk of
tormentil has only five. There is an intermediate form, too, which
exactly splits the difference between the two plants in every respect;
and one can hardly doubt that tormentil is in reality only a very
slightly altered form of cinquefoil, grown woodier and more dwarfish
from its peculiar upland situation, and with one of its petals
suppressed through gradual failure of constitutional vigour. The
frequency with which the first flower on each stem recurs to the
original five-petalled form, while the material to spare remains
abundant, is very significant: the later flowers, as the material for
their formation runs short, have generally to be content with only four
petals each.

More divergent types of potentilla than these are the forms which have
their leaves (to use the technical term) pinnately, not digitately,
divided--that is to say, with the separate leaflets arranged along two
sides of a central leaf-stalk instead of radiating from a common point;
and though the white potentilla and the strawberry belong rather to the
latter or digitate division, I shall yet enter briefly into the nature
of the pinnate section, for the sake of the light which it throws by
analogy upon the evolution of our own proper subject. Commonest among
the potentillas of this divergent group in northern Europe is the
trailing silver-weed or goose-weed of our English roadsides, a pretty,
long-leaved plant, with a silvery underside, and bright golden flowers
springing from rooted joints on its creeping runners. A rarer plant is
the shrubby potentilla, which grows in bushy or stony places, especially
on mountain sides, and has accommodated itself to its special situation
by acquiring a stout woody stem. This species also has a yellow flower.
But there are two other pinnate-leaved English potentillas whose
blossoms have long since changed colour under the selective influence of
their insect fertilisers. One of these is the marshy comarum, a
perennial which grows in peaty or boggy places, and has assumed a dingy
purplish-yellow hue, to suit the eyes of marshland insects. It is very
noticeable that waterside flies do not seem to care for yellow, and most
waterside flowers are therefore pinkish, purplish, or white. Thus the
water-crowfoot and the mud-haunting ivy-leaved crowfoot have become
white, while all our other native buttercups remain yellow. In the group
of bennets or _Geums_, closely allied to the potentillas, we find a
still closer analogy, for the roadside herb-bennet or common avens is
yellow like cinquefoil, but the marshy water-avens has exactly the same
dusky purplish-yellow tint as the marshy comarum. The other pinnate
English potentilla, found wild with us only among the clefts of the
Breiddin Hills in Montgomeryshire, is a mountain species with handsome
and conspicuous white blossoms; and this also is in striking analogy
with similar facts elsewhere, for mountain species usually rise higher
than their neighbours in the scale of colour, owing to the keen
competition between the flowers for the visits of those rare
fertilisers, the butterflies, which sail further up mountain heights
than the bees and other meadow honeysuckers. For example, some Alpine
buttercups are snowy-white, while most of their lowland congeners are
simply yellow.

With the side light thus cast upon our subject by the analogy of the
pinnate potentillas, let us hark back to the digitate cinquefoil once
more, and ask by what steps some such early ancestral form gave origin
to the common predecessor of the true strawberry and its barren sister.
The cinquefoil, we saw, had five leaflets to each leaf, but the
strawberry and the white potentilla have three only. This is one of the
marked points wherein these two plants differ from the other
potentillas, and agree with one another. But though the trefoil leaf is
a matter of some importance, as indicating community of origin, it is
not difficult to understand how it has been developed from the primitive
cinquefoil. The exact number of leaflets in a leaf is always rather
variable, depending partly on the mode of growth of the plant, and
partly on the amount of available material. Thus, in the allied
tormentil the lower leaves have five leaflets, but the upper ones have
usually three only. In the spring potentilla, a rare English species,
the lower leaves have seven or five, and the upper ones five or three.
Again, where a species creeps along the ground, it is apt to have long
pinnate leaves with many leaflets, as happens, for example, with silver-
weed and many similar plants. But where the leaves grow habitually among
tall grass or choking wayside weeds, the number of leaflets is very apt
to be reduced to three, as happens, for example, with clover and lotus
among the pea-flower tribe, and with wood-sorrel among the geranium
tribe, many of whose allies have long pinnate leaves with numerous
leaflets. Now, the strawberry and the barren strawberry differ
conspicuously in habitat from the other potentillas in the fact that
they grow mainly among grass, on banks, or in hedgerow thickets. Hence
it suits them best to raise their trefoil leaves on tall stalks above
the neighbouring herbage, and thus to get at the light and air which
they require for their proper growth. Natural selection has easily
brought about this result, because in such situations those potentillas
which raised their leaves highest would best survive, while those which
trailed or crept closely along the ground would soon be starved out for
want of carbonic acid (the raw material of growth) by their surrounding
competitors.

[Illustration: images/i089.jpg]

Fig. 18. Flower of Wild Strawberry. 
Fig. 19. Flower of White Potentilla.

In another direction the ancestors of the strawberry and of the barren
strawberry also diverged from their cinquefoil predecessors, and that
was in the peculiar colour of their flowers. For some reason rather
difficult to decide, the petals have changed from yellow to white.
Difficult to decide, I say, because we do not exactly know what are the
insects which the strawberries set themselves out especially to please
or what is the peculiar nature of their specific taste. But, as a rule,
this change from yellow to white petals is an ordinary concomitant of
higher development, and it probably accompanies some change in the
insects to which fertilisation is generally due. Our own native species
have got no further in the upward course of development than white; but
two allied East Indian forms with digitate leaves, cultivated in our
flower-gardens, the Nepaul potentilla and the purple potentilla, have
risen as far in the scale of coloration as crimson and deep red.

[Illustration: images/i090.jpg]

Fig. 20. Fruit of Wild Strawberry. 
Fig. 21. Fruit of White Potentilla.

One may sum up the common points of the strawberry and the barren
strawberry somewhat as follows: Both have tall leaves of three leaflets,
raised on an elevated leaf-stalk, whereas most of their other congeners
have many leaflets. Both have white flowers, whereas most of their other
congeners have them yellow. Both have short tufted stems; in both the
leaves are clothed with silky down; and in both the leaflets are
regularly toothed at the edge in the self-same manner. On the other
hand, they differ from one another almost exclusively in the matter of
their fruit. Now, as we shall proceed to see, it is comparatively easy
to produce the change whereby a dry fruit becomes a succulent one, and
it is also comparatively easy to produce any one single change
unaccompanied by others; but it is comparatively difficult to produce
the whole set of changes whereby the two strawberries differ alike from
all their congeners. So, if we are going to make a new genus,
_Fragaria_, with a Latin name at all, we ought to make it include both
the true strawberry and the barren strawberry, while we relegate to the
genus _Potentilla_ all the other less closely related kinds. But perhaps
we shall do better if we lump them all together in a single genus,
considering that, after all, the barren strawberry does not differ more
from the remainder of the potentillas than many of these differ from one
another among themselves.

And now, how did the edible strawberry get developed from its barren
ally? Well, if we take the fruit of any potentilla, we shall find that
it consists of several small, dry, one-seeded nuts, so tiny that they
look themselves like seeds, crowded on a thick receptacle or flower
stalk, without any signs of redness or succulence. In some potentillas,
however, as the fruit ripens, this receptacle becomes a little spongy,
something like the hull of a raspberry, only without its pulpy
character. It is a common tendency of fruits to develop such pulpiness,
and sometimes they do so quite suddenly by apparently spontaneous
variation, as when an almond tree has been known to produce peach-like
fruits. But no fruit will permanently acquire such a succulent character
unless it derives some benefit by doing so: the change, once set up,
will only be perpetuated by natural selection if it proves of advantage
to the plants which happen to display it. Has it done so in the case of
the strawberry?

A strawberry, as we all know, consists of a swollen red receptacle or
end of the flower-stalk, dotted over with little seed-like nuts, which
answer to the tiny dry fruits of the potentilla. Suppose any ancestral
potentilla ever to have shown any marked tendency towards fleshiness in
the berry, what would happen? It would probably be eaten by small
hedgerow birds, who would swallow and digest the pulp, but would not
digest the seed-like nuts embedded in its midst. Hence the nuts would
get carried about from place to place and dropped by the birds in
hedgerows or woods, under circumstances admirably adapted for their
proper germination. Supposing this to happen often, the juiciest berries
would get most frequently eaten, and so would produce hearty young
plants oftener than those among their neighbours which simply trusted to
dropping off casually among the herbage. Again, the birds like sweetness
as well as pulpiness, and those berries which grew most full of sugary
juices would be most likely to attract their attention. Once more, the
brightest-coloured fruits would be most easily seen among the tall
foliage of the hedgerows, and so those berries which showed any tendency
towards redness of flesh would be sure to gain a point in attractiveness
over their greener rivals. Thus at last the strawberry has grown into
the fruit that we know so well, by constant unconscious selection of the
little hedgerow birds, exerted at once in favour of the pulpiest, the
sweetest, and the ruddiest berries.

It is noticeable, too, that in all these particulars what happens to the
strawberry happens also in a hundred other independent cases. Wherever
animals are to be enticed by plants, sugar is sure to be developed to
entice them. It is so developed in the honey of flowers, in the extra-
floral nectaries used for attracting ants, and in the sweet secretion by
which the pitcher plants allure flies into their murderous vessels. So,
too, bright colour is commonly employed to advertise the sweet material,
as in the petals of flowers, the skin of fruits, and the pink or purple
patches on the lips of the pitcher plants. On the other hand, the
particular way in which these allurements are displayed by the
strawberry is very different from that adopted by almost all other
fruits. In the closely allied raspberry, the pulpiness and colour are
produced in the outer coat of the little nutlets themselves, and the
receptacle assumes the form of the hull, which we pull out of the fruit
and throw away. In the plum, there is only one such berry, inclosing a
single seed. But in the strawberry, the separate fruits remain always
hard and dry, and it is only the receptacle which holds them that swells
out into the bright-coloured and juicy edible portion.

It very seldom happens, however, that a plant which has diverged from
another in one point remains constant in all other points. In the
strawberry this is almost the case, for it hardly differs at all in any
particular, save its fruit, from its ancestor, the white potentilla; and
that is good evidence, it seems to me, that the two plants cannot very
long have separated from one another. Yet even here there are a few
inconspicuous lateral differences. Most notable of these are the
variations in the flower. Though to a casual observer the two blossoms
look almost identical, and the plants can only readily be identified
when in fruit, a botanical eye has never any difficulty in
distinguishing the one from the other. The petals of the barren
strawberry are usually short and narrow, the flowers scarcely open into
more than a cup shape, and there is a good deal of yellowish or reddish
colour about the receptacle and the base of the stamens. In the true
wild strawberry, on the other hand, the petals are usually larger,
rounder, and purer white, the flowers open into a wide saucer shape, and
there is no yellow or red in the centre of the blossom. Perhaps one may
best account for these changes by supposing that the true strawberry has
still further progressed in insect fertilisation. This would
sufficiently explain the purer white of the petals and the loss of such
relics of the primitive yellow hue as still remained in the barren
strawberry. But it is also probable, I think, that the barren
strawberries represent the remnants of the old ancestral race which have
not yet been lived down by the newer strawberry type, but which are
gradually undergoing progressive degradation; hence their half-opened
flowers--often self-fertilised--their smaller and degenerate petals, and
their general unattractiveness of outward appearance. It is difficult to
compare the blossom of a true wild strawberry with that of a barren
strawberry without immediately catching the obvious suggestion that the
one is going upward towards higher development and the other downward
towards general degeneracy.

In some other respects the strawberry plant equally shows itself the
nobler species of the two. Its leaves are usually larger and more erect,
its stem taller and straighter, its root-stock less fluffy and not so
creeping. Moreover, if it really descended from the white potentilla, or
from some closely allied common ancestor, it has certainly far
outstripped its progenitor in the race for the possession of the world,
for the white potentilla, or barren strawberry, is apparently a strictly
European species, found from Sweden and Ireland to the Crimea and the
Caucasus, but the true strawberry is a much more cosmopolitan plant,
being found in almost all the temperate regions of the world, from
Siberia and Scotland to Vancouver's Land, and from the Arctic Regions to
the Andes of Chili. This is quite what one would expect under the
circumstances; for while the seed-like fruits of the white potentilla
could only fall on the ground close to the mother plant, and so could
disperse themselves very slowly over a single continent, the little nuts
of the strawberry could be carried by birds from land to land, across
the severing ocean or the intervening tropical region. Thus the old
degenerate type is now apparently dying out in northern and western
Europe; but the progressive and advancing strawberry is making its way
steadily, like a colonising race, round the entire girdle of the two
temperate regions.

The strawberries are, as yet, it would seem, a relatively new race, and
so they have not, so far, split up into any very marked or distinctive
separate species. Still they have even now assumed several minor forms,
worthy at least to be distinguished as nameable varieties. The most
divergent of these, as might be expected, is the Chilian pine
strawberry, for in the southern hemisphere the imported strawberry,
carried over at first, no doubt, by some weather-driven bird, has found
itself in the midst of a very different environment from that which
surrounds it in the hedgerows and meadows of its European home: and to
this environment it has had to adapt itself in several minor but obvious
particulars. An almost equally distinct variety is the white Alpine
strawberry, which has quite lost the native blushing ruddiness of the
lowland fruit. Curiously different in another way is the hautboy, a
taller plant, with fewer and larger blossoms and a richer flavour,
chiefly distinguished by the separation of its sexes on distinct plants,
for here the stamens grow on one vine, and the pistils, or embryo
fruits, on another. In order to make the berries swell and ripen, it is
necessary to plant both sorts together, and then the fertilising insects
unconsciously carry the pollen from the staminate flowers to the
sensitive surface of their pistillate neighbours, and so assist the
efforts of the gardener in setting the fruit. In the great American
market gardens it is usual to plant one row of 'barren' flowers for
every three rows of 'fertile' ones, leaving the insects to do the rest.
At present none of these varieties can be said to have developed into
what old-fashioned botanists used to call 'a good species,' for fertile
cross-breeds can still be readily produced between them all by
artificially fertilising the pistils of one sort with pollen taken on a
camel's-hair brush from the stamens of another. The possibility of
fertile hybridisation in such a manner shows that the plants have not
long diverged from the common central stock. But after they have long
been exposed to varying circumstances and acted upon by natural
selection, they will probably become so different from one another in a
variety of small particulars that the hybrids will no longer prove
fertile, owing to the want of sufficient similarity between the
respective ancestral lines. Perfect fertility is only possible between
individuals which still retain all the principal traits of a common
ancestral form. Curiously enough, one existing variety, the Himalayan
strawberry, has actually reverted to the primitive yellow flowers of its
cinquefoil allies.

On the other hand, if the strawberries ever really live down the white
potentillas, so that the latter race dies out altogether, then the
distance between the genus _Fragaria_ and the genus _Potentilla_ will be
far greater than it is at the present day. We are lucky enough at this
moment to be able to trace the close connection between one rather
abnormal potentilla (the barren strawberry) and the true strawberry
itself. But if the barren strawberry and the Himalayan kind were to
disappear we should have no link between the yellow-flowered, five-
leaved, dry-fruited cinquefoil and the white-flowered, three-leaved,
succulent-fruited strawberry. In nature, as it now stands, the 'missing
link' is fortunately not yet missing. Though still essentially a
potentilla in all important points, it yet approaches so nearly to the
true strawberry that only rather close observation enables us to
perceive their differences in certain stages of their existence. What
thus happens now with the strawberry has doubtless happened at one time
or another with every new species of plant or animal; but the special
interest of this case consists in the fact that here, in all
probability, we still have the parent type living on in a degraded form
side by side with its more advanced and developed descendant.

* * *

## IV.

### _CLEAVERS._[5]

[Illustration: images/i101.jpg]

Fig. 22.--Goose-grass or Cleavers.

Sitting here on the gate that leads into the Fore Acre, I have just
disentangled from my nether integuments a long trailing spray of
clinging goose-grass, which has fastened itself to my legs by the
innumerable little prickly hooks that line the angles of its four-
cornered stem. It is well forward for the time of year, thanks to our
wonderfully mild and genial winter; for it is already thickly covered
with its tiny white star-shaped flowers, which have even set here and
there into the final mature stage of small burr-like fruits. Goose-
grass, or cleavers, as we ordinarily call it, is one of the very
commonest among English weeds, and yet I dare say you never even heard
its name till I told it to you just now; for it is an inconspicuous,
petty sort of plant, which would never gain any attention at all if it
were not for its rough clinging leaves, that catch one's fingers
slightly when drawn through them, and often obtrude themselves casually
upon one's notice by looping themselves in graceful festoons about one's
person. Now I am glad to have got you button-holed here upon the gate,
because I can tell you all about the goose-grass as we sit on the top
bar without risk of interruption; and I dare say you will be quite
surprised to learn that a very interesting and historical plant it is
after all, in spite of its uninviting external aspect. You will find
that its prickly leaves its square stem, its white flowers, and its odd
little fruit all tell us some curious incident in its past evolution,
and are full of suggestiveness as to the general course of plant
development. Here is our weed in abundance, growing all along the
hedgerow by our side, and clambering for yards from its root over all
the bushes and shrubs in the thicket. Pick a piece for yourself before I
begin, and then you can follow my preaching at your leisure, with the
text always open before you for reference and verification.

[Illustration: images/i103.jpg]

Fig 23.

Seedling of Cleavers.

Of course goose-grass had not always all its present marked
peculiarities. Like every other living thing, it has acquired its
existing shape by slow modification from a thousand widely different
ancestral forms. One of the best ways to discover certain lost links in
the pedigree of plants or animals is to watch the development of an
individual specimen from the seed or the egg; for the individual, we
have all often been told, to some extent recapitulates in itself the
whole past history of its race. Thus the caterpillar shows us an early
ancestral form of the butterfly, while it was still a wingless grub; and
the tadpole shows us an early ancestral form of the frog, while it was
still a limbless mud fish. So, too, the chick hatching within the shell
goes through stages analogous to those of the fish, the amphibian, the
reptile, and the bird successively. In just the same way young plants
pass through a first simple shape which helps us to picture to ourselves
what they once were--what, for example, the ancestors of the goose-grass
looked like, long before they were goose-grasses at all. Now here in my
hand I have got a young specimen in its very earliest stage, which
closely reproduces the primitive type of its first progenitors, a
million ages since. Goose-grass is an annual weed: it dies down utterly
every autumn, and only reproduces itself by seed in the succeeding
spring; but this year the weather has been so exceptionally warm and
summer-like that thousands of young plants have sprouted from the seed
ever since Christmas; and among them is the specimen which I have just
picked, and which you may have for examination if you will take the
trouble. Look into it, and you will see that its two first leaves are
quite unlike the upper ones--a phenomenon which frequently occurs in
seedling plants, and with which you are probably familiar in the case of
the pea and of the garden bean. But this difference is always a
difference in one direction only; the first leaves which come out of the
seed are invariably simpler in shape and type than all the other leaves
which come after them. In the language of science they are less
specialised; they represent an earlier and undeveloped form of leaf--
nature's rough sketch, so to speak, while the later foliage represents
the final improvements introduced with time, and perfected by the action
of natural selection.

These large oval leaves which you see in the seedling are mere general
models or central ideas of what a leaf should be; they are quite
unadapted to any one special or definite situation. They are not divided
into many little separate leaflets, or prolonged into points and angles,
or gracefully vandyked round the edges, or beautifully cut out into
lace-like patterns, or armed at every rib with stout defensive prickles,
like many other leaves that you know familiarly. Their outline is quite
simple and unbroken; they preserve for us still the extremely plain
ancestral form from which such different leaves as those of the horse-
chestnut, the oak, the clover, the milfoil, the parsley, and the holly
are ultimately derived. An expanded oval, something like this, is the
prime original, the central point from which every variety of foliage
first set out, and from which they have all diverged in various
directions, according as different circumstances favoured or checked
their development in this, that, or the other particular. Just as a
single little cartilaginous mud-haunter--a blind and skulking small
creature, something like a lancelet, something like a tadpole, and
something like the famous ascidian larva--has gradually evolved, through
diverse lines, all the existing races of beasts, birds, reptiles, and
fishes, so too a single little primæval plant, something like these two
lowest leaves of the goose-grass, has gradually evolved all the oaks and
elms and ashes; all the roses, and geraniums, and carnations; all the
cabbages, and melons, and apples, which we see in the world around us at
the present day. And, again, just as the larval form of the ascidian and
of the frog still preserves for us a general idea of that earliest
ancestral vertebrate, so too these larval leaves of the goose-grass, if
I may venture so to describe them, still preserve for us a general idea
of that earliest dicotyledonous plant.

Dicotyledonous is a very ugly word, and I shall not stop now to explain
it from the top of a five-barred gate. It must suffice if I tell you
confidentially that the little plant we have ideally reconstructed was
the first ancestor of almost all the forest trees, and of all the best
known English herbs and flowers; but not of the lilies, the grasses, and
the cereal kinds, which belong to the opposite or monocotyledonous
division of flowering plants. When this sprig of goose-grass first
appeared above the ground, it probably represented that typical ancestor
almost to the life; for it had then only the two rounded leaves you see
at its base, and none of these six-rowed upper whorls, which are so
strikingly different from them. Now, how did the upper whorls get there?
Why, of course they grew, you say. Yes, no doubt, but what made them
grow? Well, the first pair of leaves grew out of the seed, where the
mother plant had laid by a little store of albumen on purpose to feed
them, exactly as a reserve of food materials is laid by in the egg of a
hen to feed the growing chick. Under the influence of heat and moisture
the seed began to germinate, as we call it--that is to say, oxygen began
to combine with its food stuffs, and motion or sprouting was the natural
result. This motion takes in each plant a determinate course, dependent
upon the intimate molecular structure of the seed itself; and so each
seed reproduces a plant exactly like the parent, bar those small
individual variations which are the ultimate basis of new species--the
groundwork upon which natural selection incessantly works. In the case
of this goose-grass seed the first thing to appear was the pair of
little oval leaves; and, as the small store of albumen laid by in the
seed was all used up in producing them, they had to set to work at once
manufacturing new organic material for the further development of the
plant. Luckily they happened to grow in a position where the sunlight
could fall upon them--a good many seedlings are more unfortunate, and so
starve to death at the very outset of their careers--and by the aid of
the light they immediately began decomposing the carbonic acid of the
air and laying by starch for the use of the younger generation of
leaves. At the same time the vigorous young sap carried these fresh
materials of growth into the tiny sprouting bud which lay between them,
and rapidly unfolded it into such a shoot as you see now before you,
with level whorls of quite differently shaped and highly developed
leaves, disposed in rows of six or eight around the stem.

Observe that the adult type of leaf appears here suddenly and as it were
by a leap. If we could reconstruct the whole past history of the goose-
grass, we should doubtless find that each change in its foliage took
place very gradually, by a thousand minute intermediate stages. Indeed,
many of these stages still survive for us among allied plants. But the
impulsive goose-grass itself clears the whole distance between the
primitive ancestor and its own advanced type at a single bound. The
intermediate stages are all suppressed. This is not always the case:
there are many plants which begin with a simple type of leaf, and
gradually progress to a complex one by many small steps; just as the
tadpole grows slowly to be a frog by budding out first one pair of legs
and then another, and next losing his tail and his gills, and finally
emerging on dry land a full-fledged amphibian. The goose-grass, however,
rather resembles the butterfly, which passes at once from the creeping
caterpillar to the complete winged form, all the intermediate stages
being compressed into the short chrysalis period; only our plant has not
even a chrysalis shape to pass through. It is in reality a very advanced
and specially developed type--the analogue, if not of man among the
animals, at least of a highly respectable chimpanzee or intelligent
gorilla--and so it has learnt at last to pass straight from its embryo
state as a two-leaved plantlet to its typical adult form as a trailing,
whorled, and prickly creeper.

And now let us next look at this adult form itself. Here I have cut a
little bit of it for you with my penknife, and, if you like, I will lend
you my pocket lens to magnify it slightly. The fragment I have cut for
you consists of a single half-inch of the stem, with one whorl of six
long pointed leaves. You will observe, first, that the stem is
quadrangular, not round; secondly, that the leaves are lance-shaped, not
oval; and thirdly, that both stem and leaves are edged with little sharp
curved prickles, pointing backward the opposite way to the general
growth of the plant. Let us try to find out what is the origin and
meaning of these three marked peculiarities.

[Illustration: images/i109.jpg]

Fig. 24.--Stem of Cleavers.

To do so rightly we must begin by considering the near relations of the
goose-grass. In a systematic botanical classification our plant is
ranked as one of the stellate tribe, a subdivision of the great family
of the Rubiaceæ, or madder kind. Now, the stellates are so called
because of their little star-shaped flowers, and they are all
characterised by two of these goose-grass peculiarities--namely, the
square stems and the whorled leaves--while the third point, the
possession of recurved prickles on the angles of the stalk and the edges
of the leaves, is a special personal habit of the goose-grass species
itself, with one or two more of its near relations. It will be best for
us, therefore, to ask first what is the origin and meaning of the
characteristics which our plant shares with all its tribe, and
afterwards to pass on to those which are quite confined to its own
little minor group of highly evolved species.

What, then, is the use to the goose-grass of these small, narrow,
thickly whorled leaves? Why are they not all and always large, flat, and
oval, like the two seed leaves? The answer must be sought in the common
habits of all the stellate tribe. They are without exception small,
creeping, weedy plants, which grow among the dense and matted vegetation
of hedgerows, banks, heaths, thickets, and other very tangled places.
Now, plants which live in such situations must necessarily have small or
minutely subdivided leaves, like those of wild chervil, fool's parsley,
herb-Robert, and fumitory. The reason for this is clear enough. Leaves
depend for their growth upon air and sunlight: they must be supplied
with carbonic acid to assimilate, and solar rays to turn off the oxygen
and build up the carbon into their system. In open fields or bare
spaces, big leaves like burdock, or rhubarb, or coltsfoot can find food
and space; but where carbonic acid is scarce, and light is intercepted
by neighbouring plants, all the leaves must needs be fine and divided
into almost thread-like segments. The competition for the carbon under
such circumstances is exceedingly fierce. For example, in water only
very small quantities of gas are dissolved, so that all submerged water-
plants have extremely thin waving filaments instead of flat blades; and
one such plant, the water-crowfoot, has even two types of foliage on the
same stem--submerged leaves of this lace-like character, together with
large, expanded, floating leaves which loll upon the surface something
like those of the water-lily. In the same way hedgerow weeds, which
jostle thickly against one another, have a constant hard struggle for
the carbon and the sunshine, and grow out accordingly into numerous
small subdivided leaflets, often split up time after time into segments
and sub-segments of the most intricate sort. I do not mean, of course,
that each individual leaf has its shape wholly determined for it by the
amount of sun and air which it in particular happens to obtain, but that
each species has slowly acquired by natural selection the kind of leaf
which best fitted its peculiar habitat. Those plants survive whose
foliage adapts them to live in the circumstances where it has pleased
nature to place them, and those plants die out without descendants whose
constitution fails in any respect to square with that inconvenient
conglomeration of external facts that we call their environment.

[Illustration: images/i112.jpg]

Fig. 25. Interpetiolar Stipules.

That is why the goose-grass and the other stellate weeds have foliage of
this minute character, instead of broad blades like the two seed leaves.
But all plants of tangly growth do not attain their end in precisely the
same manner. Sometimes one plan succeeds best and sometimes another. In
most cases the originally round and simple leaf gets split up by gradual
steps into several smaller leaflets. In the stellate tribe, however, the
same object is provided for in a widely different fashion. Instead of
the primitive leaf dividing into numerous leaflets, a number of organs
which were not originally leaves grow into exact structural and
functional resemblance to those which were. Strictly speaking, in this
whorl of six little lance-shaped blades, precisely similar to one
another, only two opposite ones are true leaves; the other four are in
fact, to use a very technical term, interpetiolar stipules. A stipule,
you know, of course, is a little fringe or tag which often appears at
the point where the leaf stalk joins the stem, and its chief use seems
to be to prevent ants and other destructive insects from creeping up the
petiole. But in all the stellate plants the two little stipules on each
side of each leaf have grown gradually out into active green foliar
organs, to supplement and assist the leaves, until at last they have
become as long and broad as the original leaflets, and have formed with
them a perfect whorl of six or eight precisely similar blades. How do we
know that? you ask. In this simple way, my dear sir. The other Rubiaceæ
--that is to say, the remainder of the great family to which the
stellate tribe belongs--have no whorls, but only two opposite leaves;
and we have many reasons for supposing that they represent the simpler
and more primitive type, from which the stellate plants are specialised
and highly developed descendants. But between the opposite leaves grow a
pair of small stipules, occupying just the same place as the whorled
leaflets in the goose-grass; and in some intermediate species these
stipules have begun to grow out into expanded green blades, thus
preserving for us an early stage on the road towards the development of
the true stellates. Accordingly, we are justified in believing that in
the whorls of goose-grass the same process has been carried a step
further, till leaves and stipules have at last become almost
indistinguishable.

There is, however, one way in which we can still distinguish the
original true leaves of each whorl from the leaf-like stipules. Only two
leaves out of the six ever have buds or branches proceeding from their
axils; and this last token infallibly marks out for us which are the
real primitive opposite pair, and which the spurious imitation.

What may be the use of the square stem it would be more difficult to
decide. Perhaps it may serve to protect the plant from being trodden
down and broken; perhaps by its angularity and stringiness it may render
it unpalatable to herbivorous animals. This much at least is certain,
that very few cows or donkeys will eat goose-grass. There is another
large family of plants--the dead-nettle tribe--all of which have also
square stems; and they are similarly rejected as fodder by cattle.
Indeed, the very fact that the stellate tribe have become thus
quadrangular, while the other and earlier members of the madder kind,
like coffee and gardenia, have round stems, in itself suggests the idea
that there must be some sufficient reason for the change, or else it
would never have taken place; but, as in many other cases, what that
reason may be I really cannot with any confidence inform you from my
simple professional chair on the gate here. If I were only at Kew
Gardens, now--well, that might be a different matter.

And now let us come down to the individual peculiarities of the goose-
grass, and ask what is the use of the wee recurved prickles which you
can see thickly scattered on the stalk and whorls by the aid of my
pocket lens. You observe that they occur all along each angle of the
stem, and around the edge and midribs of the leaflets as well. If you
try to pull a bit of goose-grass out of the thicket entire, you will
soon see the function they subserve. The plant, you notice, resists your
effort at once; the little prickles catch securely on to the bushes and
defeat all endeavours to tear it away. It is these prickles, indeed,
which are the _raison d'être_ of the goose-grass as a separate species:
they mark it off at once from almost all the other members of the same
group. There are many allied kinds of galium in England (for galium is
the botanical name of the genus), with very similar leaves and flowers,
but they all grow in shorter bunches and frequent less thickly populated
situations. Goose-grass, however, has survived and become a distinct
kind just in virtue of these very hooks. By their aid it is enabled to
scramble for many feet over hedges and bushes, though it is but an
annual plant; and it thus makes use of the firm stem of yonder hawthorn
and this privet bush by our sides to raise its leaves into open sunny
situations which it could never reach with its own slender stalk alone.
Such an obvious improvement gives it an undoubted advantage in the
struggle for life, and so in its own special positions it has fairly
beaten all the other galiums out of the field. One of its common English
names--Robin Run-the-hedge--sufficiently expresses the exact place in
nature which it has thus adapted itself to fill and to adorn.

But how did the goose-grass first develop these little prickles? That is
the question. Granting that their possession would give it an extra
chance in the struggle for existence, if once they were to occur, how
are we to account for their first beginning? In this way, as it seems to
me. Viewed structurally, the stout little hooks which arm the stem and
leaves are only thickened hairs. Now hairs, or long pointed projections
from the epidermis, constantly occur in almost all plants, and in this
very family they are found on the edges of the leaflets and on the
angles of the stem among several allied species. But such hairs may
easily happen to grow a little thicker or harder, by mere individual or
constitutional variation; and in a plant with habits like the goose-
grass every increase in thickness and hardness would prove beneficial,
by helping the festoons to creep over the bushes among which they live.
Thus generation after generation those incipient goose-grasses which
best succeeded in climbing would set most seed and produce most young,
while the less successful would languish in the shade and never become
the proud ancestors of future plantlets. Even the less highly developed
species, such as the wall galium and the swamp galium, have little
asperities on the edge of the stem; but, as they need to climb far less
than the hedgerow goose-grass, their roughnesses hardly deserve to be
described as prickles. Our own special subject, on the other hand, being
a confirmed creeper, finds the prickles of immense use to it, and so has
developed them to a very marked extent. The corn galium, too, which
clings to the growing haulms or stubble of wheat, has learnt to produce
very similar stout hooks; while the wild madder, which I suspect is far
more closely related to goose-grass than many other plants artificially
placed in the same genus, has prickles of like character, but much
larger, by whose aid it trails over bushes and hedges for immense
distances.

After the leaves and stem we have to consider the nature of the flower.
Look at one of the blossoms on the piece I gave you, and you will easily
understand the main points of its structure. You notice that it consists
of a single united corolla, having four lobes joined at the base instead
of distinct and separate petals, while the centre of course is occupied
by the usual little yellow knobs representing the stamens and pistil.
Each goose-grass plant produces many hundreds of such flowers, springing
in small loose bunches from the axils of the leaves. What we have to
consider now is the origin and meaning of the parts which make them up.

[Illustration: images/i118.jpg]

Fig. 26.--Single flower of Cleavers.

We have already seen in dealing with the daisy that the really important
organs of the blossom are the little central yellow knobs, which do all
the active work of fertilising the ovary and producing the seeds. The
stamens, as we then observed, manufacture the pollen, and when the
pistil is impregnated with a grain of this golden dust the fruit begins
to swell and ripen. But the corolla or coloured frill around the central
organs, which alone is what we call a flower in ordinary parlance, shows
that the goose-grass is one of those plants which owe their
fertilisation to the friendly aid of insects. Blossoms of this sort
usually seek to attract the obsequious bee or the thirsty butterfly by a
drop of honey in their nectaries, supplemented by the advertising
allurements of a sweet perfume and a set of coloured petals. So much
knowledge about the functions of flowers in general we have already
acquired; the question for our present consideration is this: What gives
the goose-grass flower in particular its peculiar shape, colour, and
arrangement?

First of all, you will notice that it has a united corolla--a single
fringe of bloom instead of several distinct flower leaves. This marks
its position as a very proud one in the floral hierarchy; for you will
remember that only the most advanced blossoms have their originally
separate petals welded into a solid continuous piece. Once upon a time,
indeed, the early ancestors of our little creeper had five distinct
petals, like those of a dog-rose or a buttercup; but that was many, many
generations since. In time these petals began to coalesce slightly at
the base, so as to form a short tube as in the primrose; and, since this
arrangement made it easier for the insect to fertilise the flowers,
because he was more certain to brush his head in hunting for honey
against the pollen-bearing stamens and the sensitive summit of the
pistil, all the flowers which exhibited such a tendency gained a decided
advantage over their competitors, and lived and flourished accordingly,
while their less fortunate compeers went to the wall. So in the course
of ages such tubular flowers, like harebells and heaths, became very
common, and to a great extent usurped all the best and most profitable
situations in nature. Among them were the immediate ancestors of the
goose-grass, which had then regular long tubular blossoms, instead of
having a mere flat, disk-shaped corolla like the one you see in the
goose-grass before you. But, for a reason which I will presently tell
you, in the goose-grass tribe itself the tube has gradually become
shorter and shorter again, till at last there is nothing left of it at
all, and the corolla consists simply of four spreading lobes slightly
joined together by a little rim or margin at the base.

How do we know, you ask, that the goose-grass is descended from such
ancestral flowers having a long hollow tube? Why may it not be an early
form of tubular blossom, a plant which is just acquiring such a type of
flower, rather than one which has once possessed it and afterwards lost
it? Well, my dear sir, your objection is natural; but we know it for
this reason. I told you some time since that the other great branch of
the madder family, which had stipules instead of whorled leaves, was
thereby shown to be a more primitive form of the common type than the
stellate tribe, in which these stipules have developed into full-grown
leaves. Now, all these tropical madder-like plants have large tubular
blossoms, perfectly developed; so that we may reasonably infer the
ancestors of the goose-grass had the same sort of flowers when they were
at the same or some analogous stage of development. Moreover, amongst
the stellate plants themselves there are several which still retain the
long tubes to the blossom; and these are rather the less developed than
the more developed members of the little group. Such are the pretty blue
field-madder, which has a funnel-shaped corolla, and the sweet woodruff,
which has bell-shaped flowers. But the galiums, which are the most
advanced (or degraded) species of all, have the tube very short or
hardly perceptible, and the more so in proportion as they are most
widely divergent from the primitive type.

[Illustration: images/i121.jpg]

Fig. 27.

Flower of Field-madder.

Why, however, should a flower which was once tubular have lost its tube?
If it was an advantage to acquire such a long narrow throat, must it not
also be an advantage always to retain it? That depends entirely upon the
nature of the circumstances to which the plant must adapt itself. Now
the fact is, the original madder group seems to have had large and showy
flowers, which were fertilised by regular honey-sucking insects, such as
bees and butterflies and humming-bird hawk-moths. These are tropical
shrubs, often of considerable size, and of very different habits from
our little goose-grass. But in the temperate regions, since the earth
has begun to cool into zones, some of these rubiaceous plants have found
out that they could get along better by becoming little creeping weeds;
and these are the stellates, including our present friend. Accordingly
they have mostly given up the attempt to attract big honey-sucking
insects whose long proboscis can probe the recesses of jasmine or
woodbine, and have laid themselves out to please the small flies and
miscellaneous little beetles, which serve almost equally well to carry
their pollen from head to head. Now the flowers which specially cater
for such minor insects are usually quite flat, so that every kind alike
can get at the honey or the pollen; and that, I fancy, is why the goose-
grass and so many of its allies have lost their tubes. They are, in
fact, somewhat degenerate forms, descended from highly adapted tropical
types, but now readjusted to a humbler though more successful grade of
existence.

Closely connected with this question is the other and very interesting
problem of their colour. Why is goose-grass white? For the very same
reason--because it wishes to attract all sorts of little insects
impartially. For this purpose white is the best colour. Almost all
flowers which thus depend for fertilisation upon many different species
of winged visitors are white. And, indeed, the sort of colour in each
kind of stellate flower (as in all others) depends largely upon the sort
of insects it wishes to attract. Thus the little field-madder, which has
a long tube and is fertilised by honeysuckers of a high type, is blue or
pink, as all the family once was, no doubt, before it began to bid for
more vulgar aid. Then the lesser woodruff, or squinancy-wort, whose tube
is shorter, has white cups tinged with lilac. The goose-grass and most
of its neighbours, whose flowers have undergone still greater
degeneration, are simply white, because they wish to please all parties
equally, and white is of course the most neutral colour they could
possibly assume. Finally, the lady's bedstraw, which has no tube,
depends upon little colour-loving beetles for fertilisation, and, like
many other beetle flowers, it is bright yellow.

This order of degradation exactly reverses the upward order of chromatic
progress; for, as flowers advance in type, they pass from yellow, which
is the lowest colour, through white, pink, red, and lilac, to purple and
blue, which are the highest. And when through any special cause they
begin to retrogress, they pass backward through the same stages in
inverse order.

Again, you may have observed that I said just now the primitive ancestor
of the goose-grass had five petals. But the present united corolla has
only four lobes instead of five, and it is this arrangement, apparently,
which has gained for the whole tribe the name of stellate. Now the
tropical Rubiaceæ, which we saw reason to believe represent an earlier
stage of development than the goose-grass group, have usually five lobes
to the corolla; and in this respect they agree in the lump with the
whole great class of dicotyledonous plants to which they belong.
Therefore we may fairly conclude that to have four lobes instead of five
is a mark of further specialisation in the stellates; in other words, it
is they that have lost a lobe, not the other madder-worts that have
added one. This, then, gives us a further test of relative development--
or perhaps we ought rather to say of relative degeneration--among the
stellate tribe. Wild madder, whose flowers are comparatively large, has
usually five lobes. Yellow crosswort has most of its blossoms four-
lobed, interspersed with a few five-lobed specimens. Goose-grass
occasionally produces large five-lobed flowers, but has normally only
four lobes. The still smaller skulking species have almost invariably
four only. In fact, the suppression of one original petal seems to be
due to the general dwarfing of the flower in most of the stellate tribe.
The corolla has got too small to find room for five lobes, so it cuts
the number down to four instead. This is a common result of extreme
dwarfing. For example, the tiny central florets of the daisy ought
properly to be pinked out into five points, representing the five
primitive petals, but they often have the number reduced to four. So,
too, in the little moschatel, the outer flowers of each bunch have five
lobes, but the central one, which is crowded around and closely jammed
by the others, has regularly lost one in every case.

[Illustration: images/i126.jpg]

Fig. 28.--Strawberry and Asperula.

To show Inferior and Superior Ovaries.

There is just one more peculiarity of the goose-grass blossom which I
must not wholly overlook. You see this rough little bulb or ball beneath
the corolla, covered with incipient prickles? That is the part which
will finally grow into the fruit, after some friendly insect has brought
pollen on his legs from some neighbouring flower to impregnate the ovary
of this. Now, what I want you to notice is the fact that the future
fruit here lies _below_ the corolla--below the flower, as most of us
would say in ordinary language. But if you think of a strawberry, a
raspberry, or a poppy, you will recollect that the part which is to
become the fruit there grows _above_ the corolla, and that the petals
are inserted at its base. This last is the original and normal position
of the parts. How and why, then, has the ovary in the goose-grass kind
managed to get below the petals? Well, the process has been something
like this: When the flowers were tubular they were surrounded by a
tubular calyx, and the ovary stood in the middle of both. But in the
course of time, in order to increase the chances of successful
fertilisation, the calyx tube, the corolla tube, and the ovary in the
centre all coalesced into one solid piece--grew together, in fact, just
as the five petals had already done. So now this little bulb really
represents the calyx and ovary combined; while the corolla, only
beginning to show at the top, where it expands into its four lobes,
looks as if it started from the head of the fruit, whereas in reality it
once started at the bottom, but has now so completely united with the
calyx in its lower part as to be quite indistinguishable. Thus the fruit
is not in this plant a mere ripe form of the ovary, but is a compound
organ consisting of the calyx outside, and the ovary inside, with the
tube of the corolla quite crushed out of existence between them.

[Illustration: images/i127.jpg]

Fig. 29.

Fruit of Cleavers.

Last of all, let us look at the prickly fruit itself in its ripe
condition. Some small fly has now fertilised the head with pollen from a
brother blossom; the corolla and the stamens have fallen off; the embryo
seeds within have begun to swell; the mother plant has stocked them with
a little store of horny albumen to feed the tiny plantlets when they are
first cast forth to shift for themselves in an unsympathetic world; and
now the fruit here is almost ready to be detached from the stalk and
borne to the spot where it must make its small experiment in getting on
in life on its own account. Before I tell you how it manages to get
itself transported free of cost to a suitable situation, I should like
you to observe its shape and arrangement. It consists of two cells or
carpels united in the middle, and each of these contains a single seed.
Once upon a time there were several cells, as there still are in some of
the tropical Rubiaceæ, and each cell contained several seeds, as is the
case with many of the southern species to the present day. But when the
stellate tribe took to being small and weedy, they gave up their
additional seeds and limited themselves to one only in each cell. This
is another common result of the dwarfing process, and it is found again
in all the daisy tribe and in the umbellates, such as fool's parsley. To
make up, however, for the loss in number of the seeds in each fruit, the
number of fruits on each plant is still enormous. How many there are on
a single weed of goose-grass I have never had the patience to count, but
certainly not less than several hundred. You might find it a nice
amusement for a statistical mind to fill up this lacuna in our botanical
knowledge.

Most of the stellate plants have simple little fruits without any
special means of dispersion, but in the goose-grass the same sort of
prickles as those of the stem and leaves are further utilised for
carrying the seed to its proper place. You know seeds have many devices
for ensuring their dispersion to a distance from the mother plant. Some
are surrounded by edible pulp, as in the case of the raspberry or the
gooseberry; and these are swallowed by birds or animals, through whose
body they pass undigested, and thus get deposited under circumstances
peculiarly favourable to their germination and growth. Others have
little wings or filaments, as in the case of the dandelion or the
valerian; and these get blown by the wind to their final resting-place.
Yet others, again, are provided with hooks or prickles, like the burr
and the hounds-tongue, by whose means they cling to the wool of sheep,
the feathers and legs of birds, or the hair of animals, and thus get
carried from hedge to hedge and rubbed off against the bushes, so as to
fall on to the ground beneath. Now this last plan is especially well
adapted for a plant like the goose-grass, which lives by straggling over
low brambles and hawthorns, for it ensures the deposition of the seed in
the exact place where the full-grown weed will find such support and
friendly assistance as it peculiarly requires. Accordingly, we may be
sure that if any half-developed goose-grass ever showed any tendency to
prickliness on its fruit, it would gain a great advantage over its
neighbours in the struggle for existence, and the tendency would soon
harden under the influence of natural selection into a fixed habit of
the species. Is there any way in which such a tendency could be set up?

Yes, easily enough, as it seems to me. You remember the outer coat of
the fruit is really the calyx, and this calyx would be naturally more or
less hairy, like the original leaves. We have only to suppose that the
calyx hairs followed suit with the stem hairs, and began to develop into
stiff prickles, in order to understand how the burr-like mechanism was
first set up. Supposing it once begun, in ever so slight a degree, every
little burr which succeeded in sticking to a sheep's legs or a small
bird's breast would be pretty sure, sooner or later, of reaching a place
where its seeds could live and thrive. It is from this habit of cleaving
or sticking to one's legs that the plant has obtained one of its English
names--cleavers. Moreover, to make the development of the burr all the
more comprehensible, many of the other galiums have rather rough or
granulated fruits, while one kind--the wall galium--which in England has
smooth or warty fruit, has its surface covered in southern Europe with
stiff hairs or bristles. Another English galium besides goose-grass has
hooked bristles on its fruit, though they are not so hard or adhesive as
in our own proper subject. Thus the very steps in the evolution of the
bristly fruit are clearly preserved for us to the present day in one or
other of the allied species.

On the other hand, the very similar little corn galium, which has
prickles on its stem and leaves to enable it to cling to the growing
straw in the wheat-fields, has no hooks at all upon its fruit. Instead
of a burr it produces only little rough-looking knobs or capsules. At
first sight, this difference between the plants is rather puzzling, but
when we come to consider the peculiar habits of the corn galium we can
see at once the reason for the change. Like most other cornfield weeds,
it blossoms with the wheat, and its seed ripens with the mellowing of
the shocks. Both are cut down together, and the seed of the galium is
thrashed out at the same time as the grain. Thus it gets sown with the
seed corn from year to year, and it would only lose by having a prickly
fruit, which would get carried away to places less adapted for its
special habits than the arable fields. It has accommodated itself to its
own peculiar corner in nature, just as the goose-grass has accommodated
itself to the hedgerows and thickets. So again, in the wild madder, the
fruit, instead of becoming rough and clinging, has grown soft and pulpy,
so as to form a small blackish berry, much appreciated by birds, who
thus help unconsciously to disperse its seeds. Each plant simply goes in
the way that circumstances lead it, and that is why we get such infinite
variety of detail and special adaptation even within the narrow limits
of a single small group.

And now I think you are tired both of your seat on the gate and of my
long sermon. Yet the points to which I have called your attention are
really only a very few out of all the facts which go to make up the
strange, eventful life-history of this little creeper. If you had but
leisure and patience to hear me I might go on to point out many other
curious details of organisation which help us to reconstruct the family
pedigree of the goose-grass. There is not a single organ in the plant
which does not imply whole volumes of unwritten ancestral annals; and to
set them all forth in full would require not a single hour but a whole
course of ten or twenty sermons. Still, I hope I have done enough to
suggest to you the immense wealth of thought which the goose-grass is
capable of calling up in the mind of the evolutionary botanist; and I
trust, when you next get your clothes covered with those horrid little
cleavers, you will be disposed to think more tenderly and respectfully
than formerly of an ancient and highly developed English weed.

* * *

## V.

### _THE ORIGIN OF WHEAT._

Wheat ranks by descent as a degenerate and degraded lily. Such in brief
is the text which this paper sets out to prove, and which the whole
course of evolutionary botany tends every day more and more fully to
confirm. By thus from the very outset placing clearly before our eyes
the goal of our argument, we shall be able the better to understand as
we go whither each item of the cumulative evidence is really tending. We
must endeavour to start with the simplest forms of the great group of
plants to which the cereals and the other grasses belong, and we must
try to see by what steps this primitive type gave birth, first to the
brilliantly coloured lilies, next to the degraded rushes and sedges, and
then to the still more degenerate grasses, from one or other of whose
richer grains man has finally developed his wheat, his rice, his millet,
and his barley. We shall thus trace throughout the whole pedigree of
wheat from the time when its ancestors first diverged from the common
stock of the lilies and the water-plantains, to the time when savage man
found it growing wild among the untilled plains of prehistoric Asia, and
took it under his special protection in the little garden plots around
his wattled hut, whence it has gradually altered under his constant
selection into the golden grain that now covers half the lowland tilth
of Europe and America. There is no page in botanical history more full
of genuine romance than this; and there is no page in which the evidence
is clearer or more convincing for those who will take the easy trouble
to read it aright.

[Illustration: images/i134.jpg]

Fig. 30.

Head of Wheat.

Moreover, the case of wheat is a very interesting one, after the case of
the daisy and of cleavers, because it exhibits a different order of
evolution, that namely of continuous degradation. While the daisy has
gone constantly up, and while the goose-grass has fallen but a little
after a long course of upward development, the grasses generally have
from the very first exhibited a constant and unbroken structural
decline.

The fixed point from which we start on our inquiry is the primitive and
undifferentiated ancestral flowering plant. Into the previous history of
the line from which the cereals are ultimately descended, I do not
propose here to enter. It must suffice for our present purpose to say
dogmatically that the flowering plants as a whole derive their origin
from a still earlier flowerless stock, akin in many points to the ferns
and the club-mosses, but differing from them in the relatively important
part borne in its economy by the mechanism for cross-fertilisation. The
earliest flowering plant of the great monocotyledonous division (the
only one with which we shall here have anything to do) started
apparently by possessing a very simple and inconspicuous blossom, with a
central row of three ovaries, surrounded by two or more rows of three
stamens each, without any coloured petals or other ornamental adjuncts
of any sort. I need hardly here explain even to the unbotanical reader
that the ovaries contain the embryo seeds, and that they only swell into
fertile fruits after they have been duly impregnated by pollen from the
stamens, preferably those of another plant, or at least of another
blossom on the same stem. Seeds fertilised by pollen from their own
flower, as Mr. Darwin has shown, produce relatively weak and sickly
seedlings; seeds fertilised by pollen from a sister plant of the same
species produce relatively strong and hearty seedlings. The two cases
are exactly analogous to the effects of breeding in and in or of an
infusion of fresh blood among races of men and animals. Hence it
naturally happens that those plants whose organisation in any way
favours the ready transference of pollen from one flower to another gain
an advantage in the struggle for existence, and so tend on the average
to thrive and to survive; while those plants whose organisation renders
such transference difficult or impossible stand at a constant
disadvantage in the race for life, and are liable to fall behind in the
contest, or at least to survive only in the most unfavourable and least
occupied parts of the vegetal economy. Familiar as this principle has
now become to all scientific biologists, it is yet so absolutely
necessary for the comprehension of the present question, whose key-note
it forms, that I shall make no apology for thus once more stating it at
the outset as the general law which must guide us through all the
intricacies of the development of wheat.

Our primitive ancestral lily, not yet a lily or anything else nameable
in our existing terms, had thus to start with, one triple set of
ovaries, and about three triple sets of pollen-bearing stamens; and to
the very end this triple arrangement may be traced under more or less
difficult disguises in every one of its numerous modern descendants. It
thus differed from the primitive ancestor of dicotyledonous flowers like
the daisy and the goose-grass, which as we have seen had its parts
arranged in whorls of five, not in whorls of three, like the ancestral
lily. No single survivor, however, now represents for us this earliest
ideal stage; we can only infer its existence from the diverse forms
assumed by its various divergent modifications at the present day, all
of which show many signs of being ultimately derived from some such
primordial and simple ancestor. The first step in advance consisted in
the acquisition of petals, which are now possessed in a more or less
rudimentary shape by all the tribe of trinary flowers, or at least if
quite absent are shown to have been once present by intermediate links
or by abortive rudiments. There are even now flowers of this class which
do not at present possess any observable petals at all; but these can be
shown (as we shall see hereafter) not to be unaltered descendants of the
prime type, but on the contrary to be very degraded and profoundly
modified forms, derived from later petal-bearing ancestors, and still
connected with their petal-bearing allies by all stages of intervening
degeneracy. The original petalless lily has long since died out before
the fierce competition of its own more advanced descendants; and the
existing petalless reeds or cuckoo-pints, as well as the apparently
petalless wheats and grasses, are special adaptive forms of the newer
petal-bearing rushes and lilies.

The origin of the coloured petals, we know, is almost certainly due to
the selective action of primæval insects. The soft pollen, and perhaps
too the slight natural exudations around the early flowers, afforded
food to the ancestral creatures not then fully developed into anything
that we could distinctively call a bee or a butterfly. But as the
insects flew about from one head to another in search of such food, they
carried small quantities of pollen with them from flower to flower. This
pollen, brushed from their bodies on to the sensitive surface of the
ovaries, fertilised the embryo seeds, and so gave the fortunate plants
which happened to attract the insects all the benefits of a salutary
cross. Accordingly, the more the flowers succeeded in attracting the
eyes of their winged guests, the better were they likely to succeed in
the struggle for existence. In some cases, the outer row of stamens
appears to have become flattened and petal-like, as still often happens
with plants in the rich soil of our gardens; and in these flatter
stamens the oxidised juices assumed perhaps a livelier yellow than even
the central stamens themselves. If the flowers had fertilised their own
ovaries this change would of course have proved disadvantageous, by
depriving them entirely of the services of one row of stamens; for the
new flattened and petal-like structures lost at once the habit of
producing pollen. But their value as attractive organs for alluring the
eyes of insects more than counterbalanced this slight apparent
disadvantage; and the new petal-bearing blossoms soon outstripped and
utterly lived down all their simpler petalless allies. By devoting one
outer row of stamens to the function of alluring the fertilising flies,
they have secured the great benefit of perpetual cross fertilisation,
and so have got the better of all their less developed competitors. At
the same time, the exudations at the base of the petals have assumed the
definite form of sweet nectar or honey, a liquid which is mainly
composed of sugar, that universal allurer of animal tastes. By this
means the plants save their pollen from depredations, and at the same
time offer the insects a more effectual because a more palatable sort of
bribe.

[Illustration: images/i140.jpg]

Fig. 31.--Single flower of Alisma plantago.

Passing rapidly over these already familiar initial stages, we may go on
to those more special and distinctive facts which peculiarly concern the
ancestry of the lilies and cereals. It is probable that the nearest
modern analogue of the earliest petal-bearing trinary flowers is to be
found in the existing alisma tribe, including our own English arrowheads
and flowering rushes. As a rule, indeed, it may be said that freshwater
plants and animals tend to preserve for us very ancient types indeed;
and all the alismas are marsh or pond flowers of an extremely simple
character. They have usually three greenish sepals outside each blossom,
inclosing one whorl of three white or pink petals, two or three whorls
of three stamens each, and a number of separate ovaries, which are not
united, as in the more developed true lilies, into a single capsule, but
remain quite distinct, each with its own individual stigma or sensitive
surface. Even within this relatively early and simple group, however,
several gradations of development may yet be traced. I incline to
believe that our English smaller alisma, a not uncommon plant in wet
ditches and marshes throughout the whole of southern Britain, represents
the very earliest petal-bearing type in this line of development;
indeed, save that its petals are now pinky-white, while those of the
original ancestor were almost certainly yellow, we might almost say that
the marsh-weed in question was really the earliest petal-bearing plant
of which we are in search. It closely resembles in appearance, and in
the arrangement of its parts, the buttercups, which are the earliest
existing members of the other or quinary division of flowering plants;
and in both we seem to get a survival of a still earlier common
ancestor, only that in the one the parts are arranged in rows of three,
while in the other they are arranged in rows of five; and concomitantly
with this distinction go the two or three other distinctions which mark
off the two main classes from one another--namely, that the one has
leaves with parallel veins, only one seed-leaf to the embryo, and an
endogenous stem, while the other has leaves with netted veins, two seed-
leaves to the embryo, and an exogenous stem. Nevertheless, in spite of
such fundamental differences, we may say that the alismas and the
buttercups really stand very close to one another in the order of
development. When the two main branches of flowering plants first
diverged from one another, the earliest petal-bearing form they produced
on one divergent branch was the alisma, or something very like it; the
earliest petal-bearing form they produced on the other divergent branch
was the buttercup, or something very like it. Hence, whenever we have to
deal with the pedigree of either great line, the fixed historical point
from which we must needs set out must always be the typical alismas or
the typical buttercups. The accompanying diagram will show at once the
relation of parts in the simplest trinary flowers, and will serve for
comparison at a later stage of our argument with the arrangement of
their degraded descendants, the wheats and grasses.

[Illustration: images/i142.jpg]

_a_, ovaries; _b_, stamens, inner whorl; _c_, stamens, outer whorl; _d_,
petals; _e_, calyx-pieces.

Fig. 32.--Diagram of primitive monocotyledonous flower.

Our own smaller alisma has a number of ovaries loosely scattered about
in its centre, as in the buttercups, with two rows of three stamens
outside them, and then a single row of three petals, followed by the
calyx or inclosing cup of three green pieces. Its close ally the water-
plantain, however, shows signs of some advance towards the typical lily
form in the arrangement of its ovaries in a single ring, often loosely
divisible into three sets. And in the pretty pink flowering rush (not of
course a rush at all in the scientific sense) the advance is still more
marked in that the number of ovaries is reduced to six, that is to say,
two whorls of three each, accompanied by nine stamens, similarly
divisible into three rows. In all these very early forms (as in their
analogues the buttercups) the main point to notice is this, that there
is as yet no regular definiteness in the numerical relations of the
parts. They tend to run, it is true, in rows of three; but often these
rows are so numerous and so confused that nature loses count, so to
speak, and it is only in their higher and more developed members that we
begin to arrive at any distinct symmetry, such as that of the flowering
rush. Even here, the symmetry is far from being so perfect as in the
later lilies. There are, however, a few very special members of the
alisma family in which the approach to the true lilies is even greater.
These are well represented in England by our own common arrow-grasses--
inconspicuous little green flowers, with three calyx-pieces, three
petals, six stamens, and either six or three ovaries. Here, too, the
ovaries are at first united into a single pistil (as it is technically
called), though they afterwards separate as they ripen into three or six
distinct little capsules. One of our British kinds, the marsh arrow-
grass, has almost reached the lily stage of development; for it has
three calyx-pieces, three petals, six stamens, and three ovaries,
exactly like the true lilies; but it falls short of their full type in
the fact that its pistil divides when ripe into separate capsules,
whereas the pistil of the lilies always remains united to the very end;
and this minute difference suffices, in the eyes of systematic
botanists, to make it an alisma rather than a lily. In reality, it ought
to be regarded as a benevolent neutral--a surviving intermediate link
between the two larger classes.

[Illustration: images/i145.jpg]

Fig. 33.--Flower of White Lily and section of ovary.

The specialisation which makes the true lilies thus depends upon two
points. In the first place, all the parts are regularly symmetrical,
except that there are two rows of stamens to each one of the other
organs: the common formula being three calyx-pieces, three petals, six
stamens, and three ovaries. In the second place, the three ovaries are
completely combined together into a single three-celled pistil. The
advantage which the lilies thus gain is obvious enough. Their bright
petals, usually larger and more attractive than those of the alismas,
allure a sufficient number of insects to enable them to dispense with
the numerous stamens and ovaries of their primitive ancestors. Moreover,
this diminution in number is accompanied by an increase in effectiveness
and specialisation: for the lilies have only three sensitive surfaces to
their pistil, combined on a single stalk: and the honey is usually so
placed at its base that the insect cannot fail to brush off pollen at
every visit against all three surfaces at once. Again, while the number
of ovaries has been lessened, the number of seeds in each has been
generally increased, which also marks a step in advance, since it allows
many seeds to be impregnated by a single act of pollination. The result
of all these improvements, carried further by some lilies than by
others, is that the family has absolutely outstripped all others of the
trinary class in the race for the possession of the earth, and has now
occupied all the most favourable positions in every part of the world.
While the alismas and their allies have been so crowded out that they
now linger only in a few ponds, marshes, and swamps, to which the more
recent lily tribe have not yet had time fully to adapt themselves, the
true lilies and their yet more advanced descendants have taken seizin of
every climate and every zone upon our planet, and are to be found in
every possible position, from the arborescent yuccas and huge agaves of
the tropics to the wild hyacinths of our English woodlands and the
graceful asphodels of the Mediterranean hill-sides.

[Illustration: images/i147.jpg]

Fig. 34.--Gagea lutea.

The lilies themselves, again, do not all stand on one plane of
homogeneous evolution. There are different grades of development still
surviving among the class itself. The little yellow gagea (fig. 34)
which grows sparingly in sandy English fields may be taken as a very
fair representative of the simplest and earliest true lily type. It
bears a small bunch of little golden flowers, only to be distinguished
from the higher alismas by their united ovaries: for though both calyx
and petals are here brightly coloured, that is also the case in the
flowering rushes, and in many others of the alisma group. On the other
hand, though it may be said generally of the lilies that their calyx and
petals are coloured alike--sometimes so much so as to be practically
indistinguishable--yet there are many kinds which still retain the
greenish calyx-pieces, and that even in the more developed genera. But
most of the lilies are far handsomer than gagea and its allies: even in
England itself we have such very conspicuous and attractive flowers as
the purple fritillaries, which every Oxford man has gathered by handfuls
in the spongy meadows about Iffley lock, with their dark spotted petals
converging into a bell, and the nectaries at the base producing each a
large drop of luscious honey. Some, like our wild hyacinths, have
assumed a tubular shape under stress of insect selection, the better to
promote proper fertilisation; and at the same time have acquired a blue
pigment, to allure the eyes of azure-loving bees. Others have become
dappled with spots to act as honey-guides, or have produced brilliant
variegated blossoms to attract the attention of great tropical insects.
Our British lilies alone comprise such various examples as the lily-of-
the-valley, a tubular white scented species, adapted for fertilisation
by moths; the very similar Solomon's seal; the butcher's broom; the wild
tulip; the star-of-Bethlehem; the various squills; the asparagus; the
grape hyacinth; and the meadow saffron. Some of them (for example,
asparagus and butcher's broom) have also developed berries in place of
dry capsules; and these berries, being eaten by birds which digest the
pulp, but not the actual seeds, aid in the dispersion of the seedlings,
and so enable the plant to reduce the total number of seeds to three
only, or one in each ovary. Among familiar exotics of the same family
may be mentioned the hyacinth, tuberose, tulip, asphodel, yucca, and
most of the so-called lilies. In short, no tribe supplies us with a
greater number of handsome garden flowers, for the most part highly
adapted to a very advanced type of insect fertilisation.

Properly to understand the development of our existing wheat from this
brilliant and ornamental family, as well as to realise the true nature
of its relation to allied orders, we must first glance briefly at the
upward evolution of the other branches descended from the true lilies,
and then recur to the downward evolution which finally resulted in the
production of the degenerate grasses. In the main line of progressive
development, the lilies gave origin to the amaryllids, familiarly
represented in England by the snowdrops and daffodils, a family which is
technically described as differing from the lilies in having an inferior
instead of a superior ovary--that is to say, with the pistil apparently
placed below instead of above the point where the petals and calyx-
pieces are inserted. From the evolutionary point of view, however, this
difference (as we saw in the case of the goose-grasses) merely amounts
to saying that the amaryllids are tubular lilies, in which the tube has
coalesced with the walls of the ovary, so that the petals seem to begin
at its summit instead of at its base. The change gives still greater
certainty of impregnation, and therefore benefits the race accordingly.
At the same time, the amaryllids, being probably a much newer
development than the true lilies, have not yet had leisure to gain quite
so firm a footing in the world; though on the other hand many of them
are far more minutely adapted for special insect fertilisation than
their earlier allies. They include the so-called Guernsey lilies of our
gardens, as well as the huge American aloes which all visitors to the
Riviera know so well on the dry hills around Nice and Cannes. The iris
family are a similar but rather more advanced tribe, with only three
stamens instead of six, their superior organisation allowing them
readily to dispense with half their complement, and so to attain the
perfect trinary symmetry of three sepals, three petals, three stamens,
and three ovaries. Among them, the iris and the crocus are circular in
shape, but some very advanced types, such as the gladiolus, have
acquired a bilateral form, in correlation with special insect visits.
From these, the step is not great to the orchids, undoubtedly the
highest of all the trinary flowers, with the triple arrangement almost
entirely obscured, and with the most extraordinary varieties of
adaptation to fertilisation by bees or even by humming-birds in the most
marvellous fashions. Alike by their inferior ovary, their bilateral
shape, their single stamen, their remarkable forms, their brilliant
colours, and their occasional mimicry of insect life, the orchids show
themselves to be by far the highest of the trinary flowers, if not,
indeed, of the entire vegetable world.

From this brief sketch of the main line of upward evolution from lilies
to orchids, we must now return to the grand junction afforded us by the
lilies themselves, and travel down the other line of degeneracy and
degradation which leads us on to the grasses and the cereals, including
at last our own familiar cultivated wheat. Any trinary flower with three
calyx-pieces, three petals, six stamens, and a three-celled pistil not
concealed within an inclosing tube, is said to be a lily, as long as it
possesses brightly coloured and delicate petals. There are, however, a
large number of somewhat specialised lilies with very small and
inconspicuous petals, which have been artificially separated by
botanists as the rush family, not because they were really different in
any important point of structure from the acknowledged lilies, but
merely because they had not got such brilliant and handsome blossoms.
These despised and neglected plants, however, supply us with the first
downward step on the path of degeneracy which leads at last to the
grasses, and they may be considered as intermediate stages in the scale
of degradation, fortunately preserved for us by exceptional
circumstances to the present day. Even among the true lilies, there are
some, like the garlic and onion tribe, which show considerable marks of
degeneration, owing to some decline from the type of insect
fertilisation to the undesirable habit of fertilising themselves. Thus,
while our common English rampsons or wild garlic has pretty and
conspicuous white blossoms, some other members of the tribe, such as the
crow allium, have very small greenish flowers, often reduced to mere
shapeless bulbs. Among the true rushes, however, the course of
development has been somewhat different. These water-weeds have acquired
the habit of trusting for fertilisation to the wind, which carries the
pollen of one blossom to the sensitive surface of another, perhaps at
less trouble and expense to the parent plant than would be necessary for
the allurement of bees or flies by all the bribes of brilliant petals
and honeyed secretions. To effect this object, their stamens hang out
pensile to the breeze, on long slender filaments, so lightly poised that
the merest breath of air amply suffices to dislodge the pollen: while
the sensitive surface of the ovaries is prolonged into a branched and
feathery process, seen under the microscope to be studded with adhesive
glandular knobs, which readily catch and retain every golden grain of
the fertilising powder which may chance to be wafted toward them on the
wings of the wind. Under such circumstances, the rush kind could only
lose by possessing brightly coloured and attractive petals, which would
induce insects uselessly to plunder their precious stores: and so all
those rushes which showed any tendency in that direction would soon be
weeded out by natural selection; while those which produced only dry and
inconspicuous petals would become the parents of future generations, and
would hand on their own peculiarities to their descendants after them.
Thus the existing rushes are all plain little lilies with dry brownish
flowers, specially adapted to wind-fertilisation alone.

[Illustration: images/i154.jpg]

Fig. 35.--Single flower of Woodrush.

Among the rushes themselves, again, there are various levels of
retrogressive development--retrogressive, that is to say, if we regard
the lily family as an absolute standard; for the various alterations
undergone by the different flowers are themselves adaptive to their new
condition, though that condition is itself decidedly lower than the one
from which they started. The common rush and its immediate congeners
resemble the lilies from which they spring in having several seeds in
each of the three cells which compose their pistil. But there is an
interesting group of small grass-like plants, known as wood-rushes,
which combine all the technical characteristics of the true rushes with
a general character extremely like that of the grasses. They have long,
thin, grass-like blades in the place of leaves; and what is still more
important, as indicating an approach to the essentially one-seeded grass
tribe, they have only three seeds in the flower, one to each cell of the
capsule. These seeds are comparatively large, and are richly stored with
food-stuffs for the supply of the young plantlet. One such richly
supplied embryo is worth many little unsupported grains, since it stands
a much better chance than they do of surviving in the struggle for
existence. The wood-rushes may thus be regarded as some of the earliest
plants among the great trinary class to adopt those tactics of storing
gluten, starch, and other food-stuffs along with the embryo, which have
given the cereals their acknowledged superiority as producers of human
food. They are closely connected with the rushes, on the one hand, by
sundry intermediate species which possess thin leaves instead of
cylindrical pithy blades; and they lead on to the grasses, on the other,
by reason of their very grass-like foliage, and their reduced number of
large, well-furnished, starchy seeds.

In another particular, the rush family supplies us with a useful hint in
tracing out the pedigree of the grasses and cereals. Their flowers are
for the most part crowded together in large tufts or heads, each
containing a considerable number of minute separate blossoms. Even among
the true lilies we find some cases of such crowding in the hyacinths and
the squills, or still better in the onion and garlic tribe. But with the
wind-fertilised rushes, the grouping together of the flowers has
important advantages, because it enables the pollen more easily to fix
upon one or other of the sensitive surfaces, as the stalks sway backward
and forward before a gentle breeze. Among yet more developed or degraded
wind-fertilised plants, this crowding of the blossoms becomes even more
conspicuous. A common American rush-like water-plant, known as
eriocaulon, helps us to bridge over the gap between the rushes and such
compound flowers as the sedges and grasses. Eriocaulon and its allies
have always one seed only in each cell of the pistil: and they have also
generally a very delicate corolla and calyx, of from four to six pieces,
representing the original three sepals and three petals of the lilies
and rushes. But their minute blossoms are closely crowded together in
globular heads, the stamens and pistils being here divided in separate
flowers, though both kinds of flowers are combined in each head. From an
ancestral form not unlike this, but still more like the wood rushes, we
must get both our sedges and our grasses. And though the sedges
themselves do not stand in the direct line of descent to wheat and the
other cereals, they are yet so valuable as an illustration from their
points of analogy and of difference that we must turn aside for a moment
to examine the gradual course of their evolution.

[Illustration: images/i157.jpg]

Fig. 36. 
Fig. 37.

**Single flower of Scirpus. **
**Male and Female flower of Carex. **

The simplest and most primitive sedges now surviving, though very
degenerate in type, yet retain some distinct traces of their derivation
from earlier rush-like and lily-like ancestors. In the earliest existing
type, known as scirpus, the calyx and petals which were brightly
coloured in the lilies, and which were reduced to six brown scales in
the rushes, have undergone a further degradation to the form of six
small dry bristles, which now merely remain as rudimentary relics of a
once useful and beautiful structure. In some species of scirpus, too,
the number of these bristles is reduced from six to four or three. There
is still one whorl of three stamens, however; but the second whorl has
disappeared; while the pistil now contains only one seed instead of
three; though it still retains some trace of the original three cells in
the fact that there are three sensitive surfaces, united together at
their base into one stalk or style. Each such diminution in the number
of seeds is always accompanied by an increase in the effectiveness of
those which remain; the difference is just analogous to that between the
myriad ill-provided eggs of the cod, whose young fry are for the most
part snapped up as soon as hatched, and the two or three eggs of birds,
which watch their brood with such tender care, or the single young of
cows, horses, and elephants, which guard their calves or foals almost up
to the age of full maturity. What the bird or the animal effects by
constant feeding with worms or milk, the plant effects by storing its
seed with assorted food stuffs for the sprouting embryo.

In the more advanced or more degenerate sedges we get still further
differentiation for the special function of wind-fertilisation. Take, as
an example of these most developed types on this line of development,
the common English group of carices (fig. 37). In these, the flowers
have absolutely lost all trace of a perianth (that is to say, of the
calyx and petals), for they do not possess even the six diminutive
bristles which form the last relics of those organs in their allies, the
scirpus group. Each flower is either male or female--that is to say, it
consists of stamens or ovaries alone. The male flowers are represented
by a single scale or bract, inclosing three stamens; and in some species
even the stamens are reduced to a pair, so that all trace of the
original trinary arrangement is absolutely lost. The female flowers are
represented by a single ovary, inclosed in a sort of loose bag, which
may perhaps be the final rudiment of a tubular bell-shaped corolla like
that of the hyacinth. This ovary contains a single seed, but its shape
is often triangular, and it has usually three stigmas or sensitive
surfaces, thus dimly pointing back to the three distinct cells of its
lily-like ancestors, and the three separate ovaries of its still earlier
alisma-like progenitors. In many species, however, even this last
souvenir of the trinary type has been utterly obliterated, the ovary
having only two stigmas, and assuming a flattened two-sided shape. In
all the carices, the flowers are loosely arranged in compact spikes and
spikelets, with their mobile stamens hanging out freely to the breeze,
and their feathery stigmas prepared to catch the slightest grain of
pollen which may happen to be wafted their way by any passing breath of
air. The varieties in their arrangement, however, are almost as infinite
among the different species as those of the grasses themselves;
sometimes the male and female flowers are produced on separate plants;
sometimes they grow in separate spikes on the same plant; sometimes the
same spike has male flowers at the top and female at the bottom;
sometimes the various flowers are mixed up with one another at top and
bottom in a regular hotch-potch of higgledy-piggledy confusion. But all
the sedges alike are very grass-like in their aspect, with thin blades
by way of leaves, and blossoms on tall heads as in the grasses. In fact,
the two families are never accurately distinguished by any except
technical botanists; to the ordinary observer, they are all grasses
together, without petty distinctions of genus and species. Like the
grasses, too, the sedges are mostly plants of the open wind-swept plains
or marshy levels, where the facilities for wind-fertilisation are
greatest and most constantly present.[6]

And now, from this illustrative digression, let us hark back again to
the junction point of the rushes, whence alike the sedges and the
grasses appear to diverge. In order to understand the nature of the
steps by which the cereals have been developed from rush-like ancestors,
it will be necessary to look shortly at the actual composition of the
flower in grasses, which is the only part of their organism differing
appreciably from the ordinary lily type. The blossoms of grasses, in
their simplest form, consist of several little green florets, arranged
in small clusters, known as spikelets, along a single common axis. Of
this arrangement, the head of wheat itself offers a familiar and
excellent example. If we pull to pieces one of the spikelets composing
such a head, we find it to consist of four or five distinct florets.
Omitting special features and unnecessary details, we may say that each
floret is made up of two chaffy scales (_e_, _d_), known as pales, and
representing the calyx, together with a pair of small white petals (_c_)
known as lodicules, three stamens (_b_), and an ovary with two feathery
styles (_a_). Moreover, the two pales or calyx-pieces are not similar
and symmetrical, for the outer one (_e_) is simple and convex, while the
inner one (_d_) is apparently double, being made up of two pieces rolled
into one, and still possessing two green midribs, which show distinctly
like ribs on its flat outer surface. Here, it will immediately be
apparent, the traces of the original trinary arrangement are very slight
indeed.

[Illustration: images/i161.jpg]

Fig. 38.
Fig. 39.

**Details of flower of Wheat. **
**Flower of Wheat (glumes removed).**

But when we come to inquire into the rationale and genesis of these
curiously one-sided flowers, it is not difficult to see that they have
been ultimately derived from trinary blossoms of the rush-like type. The
first and most marked divergence from that type, for which the analogy
of the sedges has already prepared us, is the reduction of the ovary to
a single one-seeded cell, whose ripe fruity form is known as a grain. At
one time, we may feel pretty sure, there must have existed a group of
nascent grasses, which only differed from the wood-rush genus in having
a single-celled ovary instead of a three-celled pistil with one seed in
each cell; and even the ovary of this primitive grass must have retained
one mark of its trinary origin in its possession of three styles to its
one grain, thus pointing back (as most sedges still do) to its earlier
rush-like origin. That hypothetical form must have had three sepals,
three petals, six stamens, and one three-styled ovary. But the peculiar
shape of modern grass-flowers is clearly due to their very spiky
arrangement along the edge of the axis. In the wood-rushes and the
sedges, we see some approach to this condition; but in the grasses, the
crowding is far more marked, and the one-sidedness has accordingly
become far more conspicuous. Suppose we begin to crowd a number of wind-
fertilised lily-like flowers along an axis in this manner, taking care
that the stamens and the sensitive feathery styles are always turned
outward to catch the breeze (for otherwise they will die out at once),
what sort of result shall we finally get?

In the first place, the calyx, consisting of three pieces, will stand
towards the crowded stem or axis in such a fashion that one piece will
be free and exterior, while two pieces will be interior and next the
stem, thus--

O

_a a_

_a_

Now, the effect of constant crushing in this direction will be that the
two inner calyx-pieces will be slowly dwarfed, and will tend to coalesce
with one another; and this is what has actually happened with the inner
pale of wheat and of other grasses, though the midribs of the two
originally separate pieces still show on the compound pale, like dark
green lines down its centre. Thus, in the fully developed grasses, in
place of a trinary calyx, we get two chaffy scales or pales, the outer
one representing a single sepal, and the inner one, which has been
dwarfed by pressure against the stem, representing two sepals rolled
into one, with two midribs still remaining as evidence of their original
distinctness.

Next, in the case of the petals, which alternate with the sepals of the
calyx, the relation to the stem is exactly reversed; for we have here
two petals free and exterior, with one interior petal crowded closely
against the axis, thus--

O

_a_

_a a_

Here, then, the two external petals will be saved, exactly as the one
external sepal was saved in the case of the calyx; and these two petals
are represented by the very small white lodicules under the outer pale
in our existing wheats and grasses. On the other hand, the inner petal,
jammed in between the grain and the inner pale (with the stem at its
back), has been utterly crushed out of existence, partly because of its
very small size, partly because of its functional uselessness, and
partly because it had no other part with which to coalesce, and so to
save itself as the inner sepals had managed to do. Moreover, it must be
remembered that the sepals do still perform a useful service in
protecting the young flower before it opens, and in keeping out noxious
insects during the kerning or swelling of the grain; whereas the
lodicules or rudimentary petals are now apparently quite functionless;
and so we may congratulate ourselves that they are there at all, to
preserve for us the true ground-plan of the floral architecture in
grasses. Indeed, they have not survived by any means in all grasses:
among the smaller and more degraded kinds they are often wholly wanting,
having been quite crushed out between the calyx and the grain. It is
only the larger and more primitive types that still exhibit them in any
great perfection. On the other hand, one group of very large exotic
grasses, the bamboos, has three regular petals, thus clearly showing the
descent of the family as a whole from rush-like ancestors, and also
obviously suggesting that the obsolescence of the inner petal in the
other grasses is due to their small size and their closely packed minute
flowers.

Among the stamens, one-sidedness has not notably established itself, for
in wind-fertilised plants they must necessarily hang out freely to the
breeze, and therefore they do not get much crowded between the other
parts. A few grasses still even retain their double row of stamens,
having six to each floret; but most of them have only one whorl of
three. In some of the lower and more degraded forms, however, even the
stamens have lost their trinary order, and only two now survive. This is
the case in our own very degenerate little sweet-vernal-grass, the plant
which imparts its delicious fragrance to new-mown hay. But in the
cereals and in most other large species the three stamens still remain
in undiminished effectiveness to the present day.

Finally we come to the most important part of all, the ovary. This part,
alternating with the stamens, has the same arrangement of styles
relatively to the axis as in the case of the petals; and it has
undergone precisely the same sort of abortive distortion. The two outer
styles, hanging freely out of the calyx, have been preserved like the
two outer lodicules; but the inner one, pressed between the grain and
the inner pale (with the stem behind it) has been simply crushed out of
existence, like its neighbour the inner lodicule.

Thus the final result is that the whole inner portion of the flower
(except as regards stamens) has been distorted or rendered abortive by
close pressure against the stem (due to the crowding of the florets in
the spiky form), while the whole outer portion remains normal and fully
developed. We have an outer pale representing a single normal sepal, and
an inner pale representing two dwarfed and united sepals; we have two
normal outer lodicules or petals, and a blank where the inner petal
ought to be; we have three stamens, symmetrically arranged, among the
faithless faithful only found; and we have finally two normal outer
styles, with a blank in place of the absent inner style. The
accompanying diagram, compared with that of the primitive monocotyledon
(fig. 32), will make this perfectly clear.

[Illustration: images/i167.jpg]

Fig. 40.--Diagram of Wheat flower.

Here, _a_1 represents the outer pale or normal sepal, while _a_2 and
_a_3 represent the inner pale composed of the two united sepals. Again,
_b_1 and _b_2 stand for the two lodicules or surviving petals, while
_b_3 marks the place of the lost petal, now found in the bamboos alone.
The stamens are lettered _c_1, _c_2, and _c_3. The two existing styles
are shown by _d_1 and _d_2, while _d_3 marks the abortive inner style,
now not even present in a rudimentary condition. It will be observed at
once that all the outer side is normal, and all the inner side more or
less abortive through pressure against the axis.

Thus it will be seen that the line of links which connects the grasses
and cereals with the lilies is absolutely unbroken, and that it consists
throughout of one continuous course of degradation. At the same time, by
this one-sided and spiky arrangement, the grasses secured for themselves
an exceptional advantage in the struggle for existence. No other race of
small wind-fertilised plants could compete with them for the possession
of the open wind-swept plains; and over all these they spread far and
wide, rapidly differentiating themselves into a vast number of divergent
genera and species, each adaptively specialised for some peculiar
habitat, soil, or climate. At the present time, the grasses number their
kinds by thousands; they extend over the whole world from the poles to
the equator; and they form the general sward or carpet of greenery over
by far the larger portion of the terrestrial globe. Even in Britain
alone, with our poor little insular flora, a mere fragment of that
belonging to the petty European continent, we number no less than forty-
two genera of grasses, distributed into more than one hundred species.
In fact, what may fairly be called degradation from one point of view
may fairly be called adaptation from another. The organisation of the
grasses is certainly lower than that of the lilies, but it fits them
better for that station of life to which it has pleased nature to assign
them.

The various kinds of grasses differ very little from one another in
general plan; the flower in almost all is constructed strictly on the
lines above mentioned; and the leaves in almost all are just the same
soft pensile blades, making them into the proper green sward for open,
unwooded, wind-swept plains. But like almost all other very dominant
families, they have split up into an immense number of kinds,
distinguished from one another by minute differences in the arrangement
of the florets and the spikelets; and these kinds have again subdivided
into more and more minutely different genera and species. One great
group, with panicles of a loose character, and very degraded spikelets,
has given origin to many southern grasses, from some of which the
cultivated millets are derived. Another great group, with usually more
spiky inflorescence, has given origin to most of our northern grasses,
from some of which the common cereals are derived. This second group has
again split up into several others, of which the important one for our
present purpose is that of the Hordeineæ, or barley-worts. From one of
the numerous genera into which the primitive Hordeineæ have once more
split up, our cultivated barleys take their rise; from another, which
here demands further attention, we get our cultivated wheats.

The nearest form to true wheat now found wild in the British Isles is
the creeping couch-grass, a perennial closely agreeing in all essential
particulars of structure with our cultivated annual wheats. But in the
south European region we find in abundance a large series of common wild
annual grasses, forming the genus Ægilops of technical botany, and
exactly resembling true wheat in every point except the size of the
grain. One species of this genus, Ægilops ovata, a small, hard, wiry
annual, is now pretty generally recognised among botanists as the parent
of our cultivated corn. There was a good reason, indeed, why primitive
man, when he first began to select and rudely till a few seeds for his
own use, should have specially affected the grass tribe. No other family
of plants has seeds richer in starches and glutens, as indeed might
naturally be expected from the extreme diminution in the number of seeds
to each flower. On the other hand, the flowers on each plant are
peculiarly numerous; so that we get the combined advantages of many
seeds, and rich seeds, so seldom to be found elsewhere except among the
pulse family. The experiments conducted by the Agricultural Society in
their College Garden at Cirencester have also shown that careful
selection will produce large and rich seeds from Ægilops ovata,
considerably resembling true wheat, after only a few years' cultivation

Primitive man, of course, did not proceed nearly so fast as that. Of the
very earliest attempts at cultivation of Ægilops, all traces are now
lost, but we can gather that its tillage must have continued in some
unknown western Asiatic region for some time before the neolithic
period; for in that period we find a rude early form of wheat already
considerably developed among the scanty relics of the Swiss lake
dwellings. The other cultivated plants by which it is there accompanied,
and the nature of the garden weeds which had followed in its wake, point
back to Central or Western Asia as the land in which its tillage had
first begun. From that region the Swiss lake dwellers brought it with
them to their new home among the Alpine valleys. It differed much
already from the wild Ægilops in size and stature; but at the same time
it was far from having attained the stately dimensions of our modern
corn. The ears found in the lake dwellings are shorter and narrower than
our own; the spikelets stand out more horizontally, and the grains are
hardly more than half the size of their modern descendants. The same
thing is true in analogous ways with all the cultivated fruits or seeds
of the stone age: they are invariably much smaller and poorer than their
representatives in existing fields or gardens. From that time to this
the process of selection and amelioration has been constant and
unbroken, until in our own day the descendants of these little degraded
lilies, readapted to new functions under a fresh _régime_, have come to
cover almost all the cultivable plains in all civilised countries, and
supply by far the largest part of man's food in Europe, Asia, America,
and Australia.

* * *

## VI.

### _A MOUNTAIN TULIP._

The path up from the Llyn to the crest of Mynydd Mawr leads for some
distance along the mossy, boulder-strewn course of a mountain torrent,
which takes its rise in a fairy spring close below the actual summit of
the craggy peak. It is a stiff pull for fair-weather pedestrians, this
almost untrodden tourist trackway, with here and there a hand-and-knee
clamber over great glacier-marked bosses of solid granite; but the
exquisite glimpses we get at every fresh spur over the bare shoulders of
Moel Siabod and into the cleft valley of the upper Conway more than
compensate for the rough stony walking and the obvious damage to one's
nether integuments. Very few casual beaten-road visitors ever find out
these lonely footpaths up the less-frequented mountains; the mass takes
its circular tour round the regulation road by Llanberis, Beddgelert,
and Capel Curig, leaving Mynydd Mawr and its neighbouring Carnedds out
in the cool shade of popular neglect. So much the better for those
wandering naturalists who love to ramble among unhackneyed scenes, and
to spy out wild nature in all her native loveliness, an Artemis who only
bares her beauty among the deepest and most secret recesses of glade or
woodland.

[Illustration: images/i174.jpg]

Fig. 41.--Lloydia serotina

(Mountain Tulip).

Here by the bank of the tiny torrent, where I shall stop and rest on a
smooth stretch of naked rock for a few idle minutes, there is beauty
enough in all conscience to charm the spellbound eyes of any intrusive
Actæon. The moist fissures of the water-worn granite are richly clad
with filmy fronds of alpine ferns; the drier crevices among the tumbled
rocks are tufted with the black stems and graceful foliage of the
maidenhair spleenwort; and the scanty alluvial mould on the slopes
beyond is carpeted by lithe creeping sprays of beautiful branching club-
moss. All around me, a wealth of luxuriant mountain vegetation covers
the peaty soil of the hollows, or the shallow granitic clay washed down
into the crannies from the weathering crags above. There are insect-
eating sundews, with their clammy red-haired leaves inclosing the half-
digested bodies of a dozen tiny flies, whose attention they have falsely
attracted with their delusive show of pretended honey. There are equally
deceptive butterworts, with tall scapes of bright blue blossoms, and
with pale yellowish-green foliage curled tightly round their mouldering
victims in a deadly embrace. There are Alpine saxifrages, unfolding
their pretty pinky-white flowers to the eager advances of the
fertilising bees. And here amongst them all, in a sheltered nook of the
inclosing granite débris, is the great prize of the day, the wee slender
mountain tulip, in search of which I have come out this breezy morning,
and whose actual home on the side of Mynydd I hardly expected to light
upon so easily or so quickly in the upward march.

Of course I was told beforehand exactly where to look for it by the
torrent's brink; for our botanists have long ago so thoroughly
overhauled every inch of England, Scotland, Wales, and Ireland, in
search of specimens, that every individual station for every rare
British plant is perfectly well known to them, and printed in minute
detail in half a dozen British floras. But I feared that here our little
mountain tulip might be quite extinct already, exterminated by the too
pressing attention of its numerous _dilettante_ admirers; for as soon as
your average collector finds a last lingering relic of some moribund
British race on down or moorland, his first notion is to complete its
destruction by rooting up the one remaining individual as a unique
specimen, to become a permanent record of his luck and skill in the
brown paper treasuries of his own herbarium. We, however, are
naturalists of another kidney, I trust: we will observe and examine our
little treasure carefully on the spot, but we will not pull it up
ruthlessly, bulb and all, or press its pretty blossoms under a dead
weight of books and drying paper, in order to preserve its miserable
mummy in the wretched cemetery of a _hortus siccus_. Long may it
flourish on its native hill-side, and may no scientific hand ever grub
it up as the cruel trophy of a specimen-slaughtering raid! Indeed, to be
perfectly frank, like the canny Scot who was 'no thot sure of Jocky,' I
have not trusted even my readers themselves with the exact secret of my
tulip's whereabouts. I will confess that I have invented the name of
Mynydd Mawr on purpose to deceive, and I have led up to the summit by a
roundabout path through the glen of Conway in order to prevent any
future intruder from retracing his steps without me, and annexing for
his own private aggrandisement the pretty flower whose life I have so
chivalrously and humanely spared. When we come to learn the history of
its race, I feel sure every one will sympathise in the sentiment which
makes me wish to preserve this solitary colony of Alpine flowers as long
as possible from the desecrating hands of the abandoned plant-collector.

First, let us look exactly what manner of lily it really is, and then we
will go on to unravel together the clues and tokens of its romantic
history. See, it is a little simple grass-like plant, sending forth from
its buried bulb two or three very slender blades by way of leaves; and
from their midst springs a graceful bending stem, surmounted by a single
star-shaped white blossom. At least, it looks white at first sight,
though when you come to examine it more closely you can observe three
red lines running down the face of each petal, and converging on a small
bright golden spot at their base. Those lines are in fact honey-guides
for the mountain insects, pointing them the shortest road to the sweets
stored up in the nectaries, and so saving them any extra trouble in
looking about for their morning's meal. On the other hand, the insects
repay the flower for its honey by carrying pollen from blossom to
blossom, and so enabling the plant to set its seed. Of course, unless
the young capsule in the centre of each blossom is thus fertilised by
pollen from one of its neighbours, it never ripens into a seed-bearing
fruit at all; and, indeed, in the economy of the plant itself, the sole
object of the blossom, with its bright petals, its store of honey, and
its faint perfume (almost imperceptible to any save very delicate
senses), is simply to induce the bee or the butterfly thus to convey the
fertilising powder from one head of flowers to another of the same sort.

Our little plant has of course a botanical name of the usual clumsy
kind; but in this particular instance there is a certain rough fitness
in its application, for being a Welsh lily by nature it is duly known by
a Latinised Welsh name as Lloydia. Now, I am not going this morning to
inquire fully into the whole past history of the original family from
which it springs--that would be too long a subject for an off-hand
lecture as I sit here basking on the bare granite slope; I propose only
entering in any detail into the last chapter of its chequered career,
and asking how it has managed to keep its foothold for so many ages in
this one spot and on a few neighbouring Snowdonian summits. But before
we go into that final question we must just begin, by way of preparatory
exercise, with a very brief account of its earlier origin. _Lloydia
serotina_, then, to give it the full benefit of its Latinised name, is a
mountain plant of northern and Arctic Europe, as well as of the chillier
portions of Siberia and British North America. Further south, it is
found only in the colder upland shoulders of the Alps, the Caucasus, and
the Altai range, as well as in a few other great snowy mountain systems;
but in Britain it occurs nowhere except on one or two of the higher
mountains here in North Wales. By origin, it is a very early and simple
offshoot of the great lily tribe; one of the most primitive lilies,
indeed, now existing on the face of the earth. Like all others of that
vast family, it has six petals and six stamens or pollen-bearing sacs;
but it still retains a very early form of lily flower in its open star-
shaped blossom as well as in one or two other smaller peculiarities. The
cultivated tulips of our gardens, varieties of a wild Levantine species,
are all descended from a somewhat similar form; but with them the course
of development has gone much further; the petals have grown far larger
and more conspicuous, in order to allure the eyes of bigger southern
insects, and the general form of the flower has become bell-shaped
instead of star-shaped, in order to ensure more safe and certain
fertilisation by these winged allies; for in a tubular blossom the
pollen is much more likely to be brushed off from the insect's head on
to the proper portion of the unripe capsule than in an open spreading
flower like our Lloydia here. Hence we may fairly say that Lloydia
represents an early ancestral form from which the modern and more
southerly tulips are nature's enlarged and improved varieties.

But how did these pretty little white lilies get here, and why do they
still remain here in their early simple form, while their southern
sisters elsewhere have been slowly modified into brilliant yellow bell-
shaped tulips? Thereby hangs a most curious and delightful tale. For I
have very little doubt that the ancestors of our pretty lilies here have
been growing uninterruptedly in the present spot for many thousands of
years, and that during all that time they have gone on reproducing
themselves by seed from time to time, without once having crossed their
stock with any of their congeners in the Arctic regions or in the great
snow-clad ranges of central Europe. Indeed, I very much doubt whether
they have ever even intermarried with their neighbours on the other
Snowdonian summits, for I think I shall be able to show good reasons for
believing that each of these little isolated colonies has lived on for
ages all by itself on each of their three scattered peaks in the North
Welsh district.

It is a curious fact, certainly, that one should find a single species
of Arctic flower reappearing at such long distances in such isolated
spots under closely similar circumstances. If we go to the great snow-
clad stretches of land which extend around the Arctic Circle in Europe,
Asia, and America, we shall everywhere find our little lily growing in
abundance close up to the line of perpetual snow, though its diverse
habitats are there divided by wide expanses of open sea. If, again, we
cross the whole of the German plains, we shall see no Lloydias in the
intervening tract; but when we reach the Alps and the Pyrenees, we shall
a second time come upon other isolated colonies of the self-same flower.
Once more, we may turn eastward, and we shall meet with it, after a long
march, among the Carpathians and the Caucasus; or we may turn westward,
and then we shall light upon it again on the craggy sides of a few
solitary Welsh mountains. How does it come that in every cold tract we
find the self-same species recurring again and again wherever the
circumstances are fitted for its growth? and how have its seeds or bulbs
been conveyed across such wide stretches of intervening sea or valley to
so many distinct and separate chilly regions?

One obvious answer might be, that under similar conditions a like flower
had everywhere been developed from some common plant of lowland or
temperate districts. But in reality such absolute similarity of
independent development never actually occurs in nature, for the various
Lloydias are not merely rather like one another, but are actually one
and the same species, as like each other (to quote our old Welsh friend
Fluellin) 'as my fingers is to my fingers.' Now, naturalists know that
such absolute identity of structure can only arise through unbroken
descent from a common origin; wherever two species are separately
descended from unlike ancestors, however close their analogies may be,
they are always at once marked off from one another by some very obvious
points of structural dissimilarity. Nor can we suppose that the seeds of
the Lloydia have been transported from one place to another by mere
accident, clinging to the legs of Arctic birds, or carried unwittingly
on the muddy heels of globe-trotting tourists. Such accidents do indeed
occasionally occur, and they account for the very fragmentary manner in
which remote Oceanic islands like the Azores or St. Helena are peopled
by waifs and strays from the fauna and flora of all neighbouring
continents. But as we have already seen in the converse case of the
hairy spurge, it would be incredible that such an accident should have
occurred over and over again in a hundred separate cases, so that every
suitable place in the whole northern hemisphere should separately, by
mere luck, have received a distinct colony of appropriate cold-climate
plants. Incredible, I should say, even if the instance of the Lloydia
stood alone without any analogues; but in fact, as I shall try to point
out by-and-by, it is only one instance out of a thousand that might be
quoted; for every Arctic land and every snow-clad Alpine peak is covered
close up to the limit of vegetation with dozens or hundreds of similar
plants, insects, and animals, which are nowhere found in all the
intervening temperate or lowland regions. Clearly all these coincidences
cannot be due to mere accident; we must seek for their reason in some
single and common fact.

See this great rounded block of smooth granite on whose solid shoulders
I am now sitting; how wonderfully grooved and polished it is, with long,
deep, rounded furrows running lengthwise across its face in the same
direction as the general dip of the Conway valley. What can have made
those curious parallel channels on its naked surface, I wonder? Any one
who has ever looked closely at the rocks about the foot of a glacier in
Switzerland will recognise at once what was the agency at work on the
granite slopes of Mynydd Mawr. Those are most undoubtedly ice-marks,
caused by the long, slow, grinding action of the superincumbent
glaciers. For of course everybody knows nowadays that there was once a
time when great glacial sheets spread over the combes and glens of
Snowdonia, as they spread to-day over the nants of Chamounix and the
buried basin of the Mer de Glace.

Dr. Croll's calculations have shown that the astronomical conjunction
necessary for the production of such a state of things must have
occurred some two hundred thousand years since; and from that date down
to eighty thousand years ago our planet kept presenting alternately
either pole to the sun during long cycles of 10,500 years each; so that,
first, the northern hemisphere enjoyed a long summer, while the southern
was enveloped for a vast distance from the Antarctic Circle in a single
covering sheet of ice; and then again the southern hemisphere had its
lengthened spell of tropical weather, while the north was turned into
one enormous Greenland down as far as the British Isles. Eighty thousand
years ago, or thereabouts, this condition of things began to change; the
climate of the north became more genial; and ever since that date our
sober planet has oscillated within gentler limits, producing only such
alternate results of annual summer and winter as those with which we
ourselves are now familiar.

When the glaciation was at its worst in the northern hemisphere, almost
the entire surface of the European continent, from Scandinavia and
Lapland, to England, Belgium, and central Germany, lay buried beneath
one unbroken sheet of permanent ice. But when the conditions were a
little less severe, local glaciers radiated from the chief mountain
bosses of Scotland, Wales, and the Isle of Man, and ground these deep
grooves and scratches on the worn surface of the denuded rock. At length
the climate began to mend slightly; and then the plants and animals of
the Arctic zone spread uninterruptedly over the whole of northern
Europe, from the limit of pack-ice to at least the southern slope of the
Alps on the Italian side. Remains of these glacial animals--Arctic
lemmings, musk sheep, white hares, reindeers, Alpine marmots, and snowy
owls--are still found among the bone-caves and river drift of the
interglacial ages in various parts of Europe, from Scandinavia to the
Tuscan grottoes. At the same time we may be pretty sure that high Arctic
or Alpine plants, adapted to a chilly climate, like the saxifrages, the
sibbaldia, the crowberry, and the Swiss veronica, spread over all the
plains and valleys of Great Britain and the neighbouring continent.

In those days, we saw good reason to believe when we were examining the
stranded southern flora of Cornwall and Devonshire, England and Ireland
were united to one another as well as to France and Holland by a broad
belt of lowland occupying what is now the bed of the two channels and
the German Ocean, so that the mammoth and the cave-bear could roam
uninterruptedly from the Yorkshire hills to the rock-shelters of the
Dordogne, and from the bogs of Connaught to the then ice-clad summits of
the Hartz and the Jura. The dark hunters of the period, who framed the
rough, chipped stone hatchets of the Abbeville drift and the beautiful
flint arrowheads of the southern French caves, could in like manner
range without let or hindrance from Kent's Hole at Torquay to the
Schwatka cavern in Moravia, and from the honeycombed cliffs of Yorkshire
valleys to the limestone grottoes among the Alpine slopes. That
distribution of land and water easily accounts for the dispersion of
Arctic and snow-line plants or animals over all the snowy regions of
northern Europe.

But as the cold began to subside, and as a warmer fauna and flora
invaded the now milder plains and valleys of central Europe, the glacial
types, being less adapted to the new conditions, began to retreat
northward towards the Arctic Circle, or upward towards the chilly
summits of the principal mountains. Slowly, age after age, the southern
plants and animals overran all the lower portions of the continent,
cutting the glacial fauna and flora in two, and established themselves
as far as the outlying peninsula of Britain, which still continued to
form an integral part of the European mainland. After most of the
Germanic types had made good their foothold even in this distant region,
however, and after the still more southern pæonies of the Steep Holme
and the rock-cistus of Torquay had established themselves under the lee
of the Cornish and Kerry mountains, on the submerged tract which then
stretched out far to the west of the Scilly Islands, the land began to
sink slowly toward sea-level; and at last an arm of the Atlantic
encircled the whole of Ireland, and still later the waters of two long
gulfs which now form the English Channel and the North Sea met together
by bursting through the narrow barrier of chalk between Dover and Cape
Blancnez. Thus Britain finally became an island group; and, being washed
on three sides by the warm current of the Gulf Stream, it acquired an
unusually high and equable temperature for a district situated so far to
the north and rising into so many chains of low mountains. But not all
the plants and animals which inhabit the continent had had time to reach
England, which has a comparatively poor fauna and flora; while still
more failed to get to Ireland before the separation; and so, the Irish
flora contains a larger proportion of Spanish and Portuguese types,
while the mass of the English flora, especially in the eastern half of
the island, is essentially Germanic.

Even after this change to more genial conditions, however, many of the
Arctic plants, though now separated by wide stretches of sea or land
from their nearest relatives elsewhere, managed to keep up a vigorous
existence in the Scotch Highlands, the Welsh hills, and the greater
summits of the Lake district. Some of them still cover vast tracts of
country in the north; as, for example, the little green sibbaldia, a
tufted Arctic trailer, whose herbage forms a chief element of the
greensward in many parts of the Highlands; or the pretty eight-petalled
dryas, which stars with its sweet white blossoms the limestone rocks of
northern England and the Ulster hills. Among the more common of these
isolated old glacial flowers in Britain are the Alpine meadow-rue, the
northern rock-cress, the Arctic whitlow-grass, the Alpine pearlwort, the
Scottish asphodel, the mossy cyphel, the mountain lady's mantle, the
purple saxifrage, and the red bearberry. Altogether, we have still more
than two hundred such Alpine or Arctic plants, stranded among our
uplands or in the extreme north of Scotland, and probably separated for
many thousand years from the main body of their kind in the Arctic
Circle or the snowy mountains of central Europe.

Our pretty little Lloydia here is far rarer in Britain than these low
mountain kinds; for it has died out utterly even in Scotland itself, and
now survives nowhere with us except on these solitary Welsh summits.
Such cases are frequent enough in Britain; for while the moderate
mountainous or Arctic species still go on thriving among the straths and
corries, the coldest kinds of all have often been pushed upward and ever
upward by the advancing tide of southern flowers till they are left at
last only on a few isolated mountain tops, where many of them are even
now in course of slowly disappearing before the steady advance of the
southern types. For example, there is a certain pretty kind of heath,
confined to northern or Arctic hill-sides, which till lately lingered on
in Britain only on the one mountain known as the Sow of Athole in
Perthshire; but of late years it has grown rarer and rarer with each
succeeding summer, until it is now probably quite extinct. It is the
natural tendency of all such small isolated colonies, whether of plants
or animals, to die slowly out; for they cannot cross freely with any of
their own kind outside the narrow limits of their own restricted
community; and by constantly breeding in and in with one another they at
last acquire such weak and feeble constitutions that they finally
dwindle away imperceptibly for want of a healthy infusion of fresh
external blood.

[Illustration: images/i191.jpg]

Fig. 42.--Lady's Slipper (Cypripedium calceolius).

If I mention a few other like cases (as well as I can remember them on
the spur of the moment, for I cannot pretend to give a complete ex-
cathedrâ list here on the slopes of Mynydd Mawr) it will help to
elucidate the origin and nature of this little colony of mountain
tulips. There is a lovely orchid, the lady's slipper, common in Siberia
and Russia, almost up to the Arctic Circle, but now found with us only
in one Yorkshire station, where, like the Perthshire heath, it is
rapidly verging to complete local extinction. Again, among one family
alone, the tufted saxifrage has now been driven to the summits of Ben
Avers and Ben Nevis; the drooping saxifrage is extinct everywhere in
Britain save on the cloudy top of Ben Lawers; the brook saxifrage
lingers on upon the same mountain, as well as on Ben Nevis and
Lochnagar; and the Alpine saxifrage, though more frequent in little
solitary groups in Scotland and the Lake district, has died out of all
Ireland save only on the bald head of Ben Bulben in Sligo. The Alpine
sow-thistle, an Arctic and snowy weed, is now dying out with us on the
tops of Lochnagar and the Clova mountains. The black bearberry yet
haunts Ben Nevis and a few other Highland peaks. The Alpine butterwort
has been driven even from the mountains in Scotland generally, but still
drags on a secluded existence in a few very northern bogs of Caithness
and Sutherland; in this respect it resembles the northern holy-grass, an
Arctic plant, which Robert Dick, the self-taught botanist of Thurso,
discovered among the high pastures near his native town. This same grass
strangely reappears in New Zealand, whither it has doubtless been
carried from Siberia by its seeds accidentally clinging to the feet of
some belated bird; but then such a solitary case in itself shows how
impossible is the explanation of the numerous Scotch and Welsh Arctic
plants as due to mere chance; for while in north European mountains
similar instances can be counted by hundreds, in New Zealand the
coincidence is very rare and almost unparalleled.

The snowy gentian, to continue our list, turns up in a good many little
Scotch colonies; but the Alpine lychnis, its companion on the mountain
pastures of the Bernese Oberland, is only now known in Britain on the
summit of Little Kilrannoch, a Forfarshire mountain, and among the crags
of Hobcartin Fell in Cumberland. The bog sandwort, everywhere a rare and
dying species, has wholly disappeared from these islands except on the
sides of the Widdybank Fell in Durham. Its ally the fringed sandwort
loiters late on the limestone cliffs of Ben Bulben in Sligo, as well as
on one solitary serpentine hill in the island of Unst among the chilly
Shetlands. A tiny pea-flower, the Alpine astragalus, has been driven
almost everywhere to the snow-line, but still survives in Scotland among
the Clova and Braemar mountains. It is on a single spot in the same
exposed Clova range, too, that the closely related yellow oxytrope still
grows in diminishing numbers; while its ally the Ural oxytrope holds its
own manfully over all the dry hills of the Highlands. I could add to
these instances many more; but lunch is waiting to be eaten in the
knapsack, and I am loth to tire the patience of my hearers with too long
a list of barren names and bare wind-swept mountain summits.

Still, I love to think that the little colony of timid shrinking
Lloydias stranded here on the granite slopes of Mynydd Mawr can push
back its pedigree in such an unbroken line to so dim and distant a
prehistoric past. Ever since the glaciers last cleared away from this
boss of smooth stone on whose broad back we are sitting, a tiny group of
our pretty mountain tulips has continuously occupied age after age this
self-same spot. Originally, no doubt, they covered the whole sides of
the mountains and stretched down far into the plains and valleys; but
gradually, as the world's weather grew warmer, they were restricted,
first, to the mountain tracts of Wales and Scotland, then to a small
Snowdonian district, and finally, even within that shrunken realm, to
two or three isolated peaks. Occasionally, I suppose, a seed from one of
the three existing Welsh colonies may be carried by accident into the
territory of the others; but it is in the highest degree improbable that
the stock has ever been reinforced for the last fifty thousand years
from any purely external body of its congeners in the higher Alps or in
the Arctic regions. The dark small men of the neolithic age, the Aryan
Celts of the bronze period, the conquering Roman from the south, the
Englishman, the Scandinavian, the Norman, all have since come, and most
of them have gone again; but the Lloydias still hold precarious
possession of their solitary remaining strongholds. An analogy from the
animal world will help to bring out the full strangeness of this
extraordinary isolation. Mount Washington in New Hampshire is the
highest peak among the beautiful tumbled range of the White Mountains.
On and near its summit a small community of butterflies belonging to an
old Glacial and Arctic species still lingers over a very small area,
where it has held its own for the eighty thousand years that have
elapsed since the termination of the great ice age. The actual summit of
the mountain rises to a height of 6,293 feet; and the butterflies do not
range lower than the five thousand feet line--as though they were
confined on Snowdon to a district between the Ordnance cairn and the
level of the little slumbering tarn of Glasllyn. Again, from Mount
Washington to Long's Peak in Colorado, the distance amounts to 1,800
miles; while from the White Mountains to Hopedale in Labrador, where the
same butterflies first reappear, makes a bee-line of fully a thousand
miles. In the intervening districts there are no insects of the same
species. Hence we must conclude that the few butterflies left behind by
the retreating main-guard of their race on that one New Hampshire peak
have gone on for thousands and thousands of years, producing eggs and
growing from caterpillars into full-fledged insects, without once
effecting a cross with the remainder of their congeners among the snows
of the Rocky Mountains or in the chilly plains of sub-Arctic America. So
far as they themselves know, they are the only representatives of their
kind now remaining on the whole earth, left behind like the ark on
Ararat amid the helpless ruins of an antediluvian world. Well, what
these Mount Washington butterflies are among insects, that are our
pretty wild tulips here among English flowers. They remain to us as
isolated relics of an order that has long passed away; and they help us
to rebuild with fuller certainty the strange half-undeciphered history
of the years that were dead and gone long before written books had yet
begun to be.

* * *

## VII.

### _A FAMILY HISTORY._

[Illustration: images/i197.jpg]

Fig. 43.--Common Cinquefoil.

Although the roses, like many other highly respectable modern families,
cannot claim for themselves any remarkable antiquity--their tribe is
only known, with certainty, to date back some three or four millions of
years, to the tertiary period of geology--they have yet in many respects
one of the most interesting and instructive histories among all the
annals of English plants. In a comparatively short space of time they
have managed to assume the most varied forms; and their numerous
transformations are well attested for us by the great diversity of their
existing representatives. Some of them have produced extremely beautiful
and showy flowers, as is the case with the cultivated roses of our
gardens, as well as with the dog-roses, the sweet-briars, the may, the
blackthorn, and the meadow-sweet of our hedges, our copses, and our open
fields. Others have developed edible fruits, like the pear, the apple,
the apricot, the peach, the nectarine, the cherry, the strawberry, the
raspberry, and the plum; while yet others again, which are less
serviceable to lordly man, supply the woodland birds or even the village
children with blackberries, dewberries, cloudberries, hips, haws, sloes,
crab-apples, and rowanberries. Moreover, the various members of the rose
family exhibit almost every variety of size and habit, from the creeping
silver-weed which covers our roadsides or the tiny alchemilla which
peeps out from the crannies of our walls, through the herb-like meadow-
sweet, the scrambling briars, the shrubby hawthorn, and the bushy bird-
cherry, to the taller and more arborescent forms of the apple-tree, the
pear-tree, and the mountain ash. And since modern science teaches us
that all these very divergent plants are ultimately descended from a
single common ancestor--the primæval progenitor of the entire rose tribe
--whence they have gradually branched off in various directions, owing
to separately slight modifications of structure and habit, it is clear
that the history of the roses must really be one of great interest and
significance from the new standpoint of evolution. I propose, therefore,
here to examine the origin and development of the existing English
roses, with as little technical detail as possible; and I shall refer
for the most part only to those common and familiar forms which, like
the apple, the strawberry, or the cabbage rose, are already presumably
old acquaintances of all my readers.

The method of our inquiry must be a strictly genealogical one. For
example, if we ask at the present day whence came our own eatable garden
plums, competent botanists will tell us that they are a highly
cultivated and carefully selected variety of the common sloe or
blackthorn. It is true, the sloe is a small, sour, and almost uneatable
fruit, the bush on which it grows is short and trunkless, and its
branches are thickly covered with very sharp stout thorns; whereas the
cultivated plum is borne upon a shapely spreading tree, with no thorns,
and a well-marked trunk, while the fruit itself is much larger, sweeter,
and more brightly coloured than the ancestral sloe. But these changes
have easily been produced by long tillage and constant selection of the
best fruiters through many ages of human agriculture. So, again, if we
ask what is the origin of our pretty old-fashioned Scotch roses, the
botanists will tell us in like manner that they are double varieties of
the wild burnet-rose which grows beside the long tidal lochs of the
Scotch Highlands, or clambers over the heathy cliffs of Cumberland and
Yorkshire. The wild form of the burnet-rose has only five simple petals,
like our own common sweet-briar; but all wild flowers when carefully
planted in a rich soil show a tendency to double their petals; and, by
selecting for many generations those burnet-roses which showed this
doubling tendency in the highest degree, our florists have at last
succeeded in producing the pretty Scotch roses which may still be found
(thank Heaven!) in many quiet cottage gardens, though ousted from
fashionable society by the Marshal Niels and Gloires de Dijon of modern
scientific horticulturists.

Now, if we push our inquiry a step further back, we shall find that this
which is true of cultivated plants in their descent from wild parent
stocks, is true also of the parent stocks themselves in their descent
from an earlier common ancestor. Each of them has been produced by the
selective action of nature, which has favoured certain individuals in
the struggle for existence, at the expense of others, and has thus
finally resulted in the establishment of new species, having peculiar
points of advantage of their own, now wholly distinct from the original
species whose descendants they are. Looked at in this manner, every
family of plants or animals becomes a sort of puzzle for our ingenuity,
as we can to some extent reconstruct the family genealogy by noting in
what points the various members resemble one another, and in what points
they differ among themselves. To discover the relationship of the
various English members of the rose tribe to each other--their varying
degrees of cousinship or of remoter community of descent--is the object
which we set before ourselves in the present paper.

Perhaps the simplest and earliest type of the rose family now remaining
in England is to be found in the little yellow potentillas which grow
abundantly in ill-kept fields or by scrubby roadsides. The potentillas
are less familiar to us than most others of the rose family, and
therefore I am sorry that I am obliged to begin by introducing them
first to my reader's notice rather than some other and older
acquaintance, like the pear or the hawthorn. But as they form the most
central typical specimen of the rose tribe which we now possess in
England, it is almost necessary to start our description with them, just
as in tracing a family pedigree we must set out from the earliest
recognisable ancestor, even though he may be far less eminent and less
well-known than many of his later descendants. For to a form very much
like the potentillas all the rose family trace their descent. The two
best known species of potentilla are the goose-weed or silver-weed, and
the cinquefoil.[7] Both of them are low creeping herb-like weeds, with
simple bright yellow blossoms about the size of a strawberry flower,
having each five golden petals, and bearing a number of small dry brown
seeds on a long green stalk. At first sight a casual observer would
hardly take them for roses at all, but a closer view would show that
they resemble in all essential particulars an old-fashioned single
yellow rose in miniature. From some such small creeping plants as these
all the roses are probably descended. Observe, I do not say that they
are the direct offspring of the potentillas, but merely that they are
the offspring of some very similar simple form. We ourselves do not
derive our origin from the Icelanders; but the Icelanders keep closer
than any other existing people to that primitive Teutonic and
Scandinavian stock from which we and all the other people of
northwestern Europe are descended. Just so, the roses do not necessarily
derive their origin from the potentillas, but the potentillas keep
closer than any other existing rose to that primitive rosaceous stock
from which all the other members of the family are descended.[8]

The strawberry is one of the more developed plants which has varied
least from this early type represented by the cinquefoil and the silver-
weed. There is, in fact, one common English potentilla, whose nature we
have already considered, and which bears with village children the
essentially correct and suggestive name of barren strawberry. This
particular potentilla differs from most others of its class in having
white petals instead of yellow ones, and in having three leaflets on
each stalk instead of five or seven. When it is in flower only it is
difficult at first sight to distinguish it from the strawberry blossom,
though the petals are generally smaller, and the whole flower less
widely opened. After blossoming, however, the green bed or receptacle on
which the little seeds[9] are seated does not swell out (as in the true
strawberry) into a sweet, pulpy, red mass, but remains a mere dry stalk
for the tiny bunch of small hard inedible nuts. The barren strawberry,
indeed, as we saw in an earlier paper, is really an intermediate stage
between the other potentillas and the true eatable strawberry; or, to
put it more correctly, the eatable strawberry is a white-flowered
potentilla which has acquired the habit of producing a sweet and bright-
coloured fruit instead of a few small dry seeds. Since we have got to
understand the _rationale_ of this first and simplest transformation, we
have now a clue by which we may interpret almost all the subsequent
modifications of the rose family, and I must therefore be permitted here
briefly to recapitulate the chief points we have already proved in this
matter.

The true strawberry, we saw, resembles the barren strawberry in every
particular except in its fruit. It is a mere slightly divergent variety
of that particular species of potentilla, though the great importance of
the variety from man's practical point of view causes us to give it a
separate name, and has even wrongly induced botanists to place it in a
separate genus all by itself. In reality, however, the peculiarity of
the fruit is an extremely slight one, very easily brought about. In all
other points--in its root, its leaf, its stem, its flower, nay, even its
silky hairs--the strawberry all but exactly reproduces the white
potentilla. It is nothing more than one of these potentillas with a
slight diversity in the way it forms its fruit. To account, therefore,
for the strawberry we had first to account for the white potentilla from
which it springs.

The white potentilla, or barren strawberry, you will remember, is itself
a slightly divergent form of the yellow potentillas, such as the
cinquefoil. From these it differs in three chief particulars. In the
first place, it does not creep, but stands erect; this is due to its
mode of life on banks or in open woods, not among grass and meadows as
is the case with the straggling cinquefoil. In the second place, it has
three leaflets on each stalk instead of five, and this is a slight
variation of a sort liable to turn up at any time in any plant, as the
number of leaflets is very seldom quite constant. In the third place, it
has white petals instead of yellow ones, and this is the most important
difference of any. All flowers with bright and conspicuous petals we
know are fertilised by insects, which visit them in search of honey or
pollen, and the use of the coloured petals is, in fact, to attract the
insects and to induce them to fertilise the seeds. Now, yellow seems to
have been the original colour of the petals in almost all (if not
absolutely in all) families of flowers; and the greater number of
potentillas are still yellow. But different flowers are visited and
fertilised by different insects, and as some insects like one colour and
some another, many blossoms have acquired white or pink or purple petals
in the place of yellow ones, to suit the particular taste of their
insect friends. In tracing the upward course of development in the
roses, we shall see that they follow the ordinary law of progressive
chromatic changes: the simpler types are yellow; the somewhat higher
ones are white; the next pink; and the highest in this particular family
are red; for no rose has yet attained to the final stage of all, which
is blue. The colours of petals are always liable to vary, as we all see
in our gardens, where florists can produce at will almost any shade or
tint that they choose; and when wild flowers happen to vary in this way,
they often get visited by some fresh kind of insect which fertilises
their seeds better than the old ones did, and so in time they set up a
new variety or a new species. Two of our English potentillas have thus
acquired white flowers to suit their proper flies, while one boggy
species has developed purple petals to meet the æsthetic requirements of
the marshland insects. No doubt the white blossoms of the barren
strawberry are thus due to some original 'sport' or accidental
variation, which has been perpetuated and become a fixed habit of the
plant because it gave it a better and surer chance of setting its seeds,
and so of handing down its peculiarities to future generations.

And now, how did we find the true strawberry had developed from the
three-leaved white potentilla? Here the birds came in to play their
part, as the bees and flies had done in producing the white blossom.
Birds are largely dependent upon fruits and seeds for their livelihood,
and so far as they are concerned it does not matter much to them which
they eat. But from the point of view of the plant it matters a great
deal. For if a bird eats and digests a seed, then the seed can never
grow up to be a young plant; and it has so far utterly failed of its
true purpose. If, however, the fruit has a hard indigestible seed inside
it (or, in the case of the strawberry, outside it), the plant is all the
better for the fact, since the seed will not be destroyed by the bird,
but will merely be dispersed by it, and so aided in attaining its proper
growth. Thus, if certain potentillas happened ever to swell out their
seed receptacle into a sweet pulpy mass, and if this mass happened to
attract birds, the potentillas would gain an advantage by their new
habit, and would therefore quickly develop into wild strawberries as we
now get them. But the difference between the strawberry fruit and the
potentilla fruit is to the last a very slight one. Both have a number of
little dry seeds seated on a receptacle; only, in the strawberry the
receptacle grows red and succulent, while in the potentilla it remains
small and stalk-like. The red colour and sweet juice of the strawberry
serve to attract the birds which aid in dispersing the seed, just as the
white or yellow petals and the sweet honey of the potentilla blossoms
serve to attract the insects which aid in fertilising the flowers. In
this way all nature is one continual round of interaction and mutual
dependence between the animal and vegetable worlds.

[Illustration: images/i209a.jpg]

Fig. 44.--Fruit of Bramble.

[Illustration: images/i209b.jpg]

Fig. 45.--Flower of Bramble.

The potentillas and the strawberry plant are all of them mere low
creeping or skulking herbs, without woody stems or other permanent
branches. But when we get to the development of the brambles or
blackberry bushes, we arrive at a higher and more respectable division
of the rose family. There are two or three intermediate forms, such as
water-avens and herb-bennet--tall, branching, weedy-looking roadside
plants--which help us to bridge over the gulf from the one type to the
other. Indeed, even the strawberry and the cinquefoil have a short
perennial, almost woody stock, close to the ground, from which the
annual branches spring; and in some other English weeds of the rose
family the branches themselves are much stiffer and woodier than in
these creeping plants. But in the brambles, the trunk and boughs have
become really woody, by the deposit of hard material in the cells which
make up their substance. Still, even the brambles are yet at heart mere
creepers like the cinquefoil. They do not grow erect and upright on
their own stems: they trail and skulk and twine in and out among other
and taller bushes than themselves. The leaves remain very much of the
cinquefoil type; and altogether there is a good deal of the potentilla
left in the brambles even now.

However, these woody climbers have certainly some fresh and more
developed peculiarities of their own. They are all prickly shrubs, and
the origin of their prickles is sufficiently simple. Even the
potentillas have usually hairs on their stems; and these hairs serve to
prevent the ants and other honey-thieving insects from running up the
stalks and stealing the nectar intended for fertilising bees and
butterflies. Similar hairs in the goose-grass grew, you will recollect,
into the little clinging hooks of the stems and midribs. But in the
brambles, hairs of the same sort have grown still thicker and stouter,
side by side with the general growth in woodiness of the whole plant; so
that they have at last developed into short thorns, which serve to
protect the leaves and stem from herbivorous animals. As a rule, the
bushes and weeds which grow in waste places are very apt to be protected
in some such fashion, as we see in the case of gorse, nettles,
blackthorn, holly, thistles, and other plants; but the particular nature
of the protection varies much from plant to plant. In the brambles it
takes the form of stiff prickly hairs; in the nettles, of stinging
hairs; in the gorse, of pointed leaves; and in the thorn-bushes of
short, sharp, barren branches.

Another peculiarity of the bramble group is their larger white flowers
and their curious granulated fruit. The flowers, of course, are larger
and whiter in order to secure the visits of their proper fertilising
insects; the fruits are sweet and coloured in order to attract the
hedgerow birds. Observe, too, that the flowers being higher in type than
those of the strawberry, are often tinged with pink: here we get the
first upward step in the direction of the true roses. The nature of the
fruit in the raspberry, the blackberry, and the dewberry, again, is
quite different from that of the strawberry. Here, instead of the
receptacle swelling out and growing red and juicy, it is the outer coat
of the separate little seeds themselves that forms the eatable part;
while the receptacle remains white and inedible, being the 'hull' or
stem which we pick out from the hollow thimble-like fruit in the
raspberry. Each little nut, which in the strawberry was quite hard and
brown, is here covered with a juicy black or red pulp, inside which lies
the stony real seed; so that a blackberry looks like a whole collection
of tiny separate fruits, run together into a single head. Moreover,
there are other minor differences in the berries themselves, even within
the bramble group; for while the raspberry and cloudberry are red, to
suit one set of birds, the blackberry and dewberry are bluish black, to
suit another set; and while the little grains hold together as a cup in
the raspberry, but separate from the hull, they cling to the hull in the
other kinds. Nevertheless, in leaves, flower, and fruit there is a very
close fundamental agreement among all the bramble kind and the
potentillas. Thus we may say that the brambles form a small minor branch
of the rose family, which has first acquired a woody habit and a
succulent fruit, and has then split up once more into several smaller
but closely allied groups, such as the blackberries, the raspberries,
the dewberries, and the stony brambles.

[Illustration: images/i213.jpg]

Fig. 46.--Vertical section of a Dog-rose.

The true roses, represented in England by the dog-rose and sweet-briar,
show us a somewhat different development from the original type. They,
too, have grown into tall bushes, less scrambling and more erect than
the brambles. They have leaves of somewhat the same sort, and prickles
which are similarly produced by the hardening of sharp hairs upon the
stem. But their flowers and fruit are slightly more specialised--more
altered, that is to say, for a particular purpose from the primitive
plan. In the first place, the flowers, though still the same in general
arrangement, with five petals and many stamens and carpels (or fruit-
pieces), have varied a good deal in detail. The petals are here much
larger, and they have advanced to the stage of a brilliant pink; while
the blossoms are also sweet-scented. These peculiarities of course serve
to attract the bees and other large fertilising insects, which thus
carry pollen from head to head, and aid in setting the seeds much more
securely than the little pilfering flies. Moreover, in all the roses,
the outer green cup which covers the blossom in the bud has grown up
around the little seeds or fruit-pieces, so that instead of a ball
turned outward, as in the strawberry and raspberry, you get, as it were,
a bottle turned inward, with the seeds on the inner side. After
flowering, as the fruit ripens, this outer cup grows round and red,
forming the hip or fruit-case, inside which are to be found the separate
little hairy seeds. Birds eat this dry berry, though we do not, and thus
aid in dispersing the species. But though they digest the soft red outer
pulp, formed by the swollen stalk, they cannot digest the hairy seed, so
the plant attains its prime object of getting them duly scattered. The
true roses, then, are another branch of the original potentilla stock,
which have acquired a bushy mode of growth, with a fruit differing in
construction from that of the brambles. Our English kinds are merely
pink; the more developed exotics are often scarlet and crimson.

We have altogether some five true wild roses in Britain. The commonest
is the dog-rose, which everybody knows well; and next comes the almost
equally familiar sweet-briar, with its delicately scented glandular
leaves. The burnet-rose is the parent of our cultivated Scotch roses,
and the two other native kinds are comparatively rare. Double garden
roses are produced from the single five-petalled wild varieties by
making the stamens (which are the organs for manufacturing pollen) turn
into bright-coloured petals. There is always more or less of a tendency
for stamens thus to alter their character; but in a wild state it never
comes to any good, because such plants can never set seed, for want of
pollen, and so die out in a single generation. Our gardeners, however,
carefully select these distorted individuals, and so at length produce
the large, handsome, barren flowers with which we are so familiar. The
cabbage and moss roses are monstrous forms thus bred from the common
wild French roses of the Mediterranean region; the China roses are
cultivated abortions from an Asiatic species; and most of the other
garden varieties are artificial crosses between these or various other
kinds, obtained by fertilising the seed vessels of one bush with pollen
taken from the blossoms of another of a different sort. To a botanical
eye, double flowers, however large and fine, are never really beautiful,
because they lack the order and symmetry which appear so conspicuously
in the five petals, the clustered stamens, and the regular stigmas of
the natural form.

From the great central division of the rose family, thus represented by
the potentillas, the strawberry, the brambles, and the true roses, two
main younger branches have diverged much more widely in different
directions. As often happens, these junior offshoots have outstripped
and surpassed the elder stock in many points of structure and function.
The first of the two branches in question is that of the plum-tribe; the
second is that of the pears and apples. Each presents us with some new
and important modifications of the family traits.

Of the plum tribe, our most familiar English examples, wild or
cultivated, are the sloe or blackthorn, with its descendant the garden
plum; as well as the cherry, the apricot, the peach, the nectarine, and
the almond. All these plants differ more or less conspicuously from the
members of the central group which we have so far been examining in
their tree-like size and larger trunks. But they also differ in another
important point: each flower contains only one seed instead of many, and
this seed is inclosed in a hard bony covering, which causes the whole
plum tribe (except only the almond, of which more anon) to be popularly
included under the common title of 'stone-fruits.' In most cases, too,
the single seed is further coated with a soft, sweet, succulent pulp,
making the whole into an edible fruit. What, now, is the reason for this
change? What advantage did the plant derive from this departure from the
ordinary type of rose-flower and rose-fruit? To answer this question we
must look at one particular instance in detail, and we cannot do better
than take that well-known fruit, the cherry, as our prime example of the
whole class.

The cherry, like the strawberry, is an eatable fruit. But while in the
strawberry we saw that the pulpy part consisted of the swollen stalk or
receptacle, in which several small dry seeds were loosely embedded, with
the cherry the pulpy part consists of the outer coat of the fruit or
seed vessel itself, which has grown soft and juicy instead of remaining
hard and dry. In this respect the cherry resembles a single grain from a
raspberry; but from the raspberry, again, it differs in the fact that
each flower produces only a single solitary one-seeded fruit, instead of
producing a number of little fruits, all arranged together in a sort of
thimble. In the raspberry flower, when blossoming, you will find in the
centre several separate carpels or fruit-pieces; in the cherry you will
find only one. The cherry, in fact, may (so far as its fruit is
concerned) be likened to a raspberry in which all the carpels or fruit-
pieces except one have become aborted. And the reason for the change is
simply this: cherry bushes (for in a wild state they are hardly trees)
are longer-lived plants than the bramble kind, and bear many more
blossoms on each bush. Hence one seed to every blossom is quite as many
as they require to keep up the numbers of the species. Moreover their
large and attractive fruits are much more likely to get eaten and so
dispersed by birds than the smaller and less succulent berries of the
brambles. Furthermore, the cherry has a harder stone around each seed,
which is thus more effectually protected against being digested, and the
seed itself consists of a comparatively big kernel, richly stored with
food-stuffs for the young plant, which thus starts relatively well
equipped in the battle of life. For all these reasons the cherries are
better off than the brambles, and therefore they can afford to produce
fewer seeds to each flower, as well as to make the coverings of these
seeds larger and more attractive to birds. Originally, indeed, the
cherry had two kernels in each stone, and to this day it retains two
little embryo kernels in the blossom, one of which is usually abortive
afterwards (though even now you may sometimes find two, as in philipoena
almonds); but one seed being ordinarily quite sufficient for all
practical purposes, the second one has long since disappeared in the
vast majority of cases.

The plum scarcely differs from the cherry in anything important except
the colour, size, and shape of the fruit. It is, as we have already
noted, a cultivated variety of the blackthorn, in which the bush has
become a tree, the thorns have been eradicated, and the fruit has been
immensely improved by careful selection. The change wrought in these two
wild bushes by human tillage shows, indeed, how great is the extent to
which any type of plant can be altered by circumstances in a very short
time. The apricot is yet another variety of the same small group, long
subjected to human cultivation in the East.

Peaches and nectarines differ from apricots mainly in their stones,
which are wrinkled instead of being smooth; but otherwise they do not
seriously diverge from the other members of the plum tribe. Indeed,
though botanists rank the apricot as a plum, because of its smooth
stone, and put the peach and nectarine in a genus by themselves, because
of their wrinkled coating, common sense shows us at once that it would
be much easier to turn an apricot into a peach than to turn a plum into
an apricot. There is one species of nectarine, however, which has
undergone a very curious change, and that is the almond. Different as
they appear at first sight, the almond must really be regarded as a very
slightly altered variety of nectarine. Its outer shell or husk
represents the pulpy part of the nectarine fruit; and indeed, if you cut
in two a young unripe almond and a young unripe nectarine, you will find
that they resemble one another very closely. But as they ripen the outer
coat of the nectarine grows juicier, while that of the almond grows
stringier and coarser, till at last the one becomes what we commonly
call a fruit, while the other becomes what we commonly call a nut. Here,
again, the reason for the change is not difficult to divine. Some seeds
succeed best by making themselves attractive and trusting to birds for
their dispersion; others succeed best by adopting the tactics of
concealment, by dressing themselves in green when on the tree, and in
brown when on the ground, and by seeking rather to evade than to invite
the attention of the animal world. Those seed vessels which aim at the
first plan we know as fruits; those which aim rather at the second we
know as nuts. The almond is just a nectarine which has gone back to the
nut-producing habit. The cases are nearly analogous to those of the
strawberry and the potentilla, only the strawberry is a fruit developed
from a dry seed, whereas the almond is a dry seed developed from a
fruit. To some extent this may be regarded as a case of retrogressive
evolution or degeneration.

The second great divergent branch of the rose family--that of the pears
and apples--has proceeded towards much the same end as the plums, but in
a strikingly different manner. The apple kind have grown into trees, and
have produced fruits. Instead, however, of the seed vessel itself
becoming soft and succulent, the calyx or outer flower covering of the
petals has covered up the carpels or young seed vessels even in the
blossom, and has then swollen out into a sort of stalk-like fruit. The
case, indeed, is again not unlike that of the strawberry, only that here
the stalk has enlarged outward round the flower and inclosed the seeds,
instead of simply swelling into a boss and embedding them. In the hip of
the true roses we get some foreshadowing of this plan, except that in
the roses the seeds still remained separate and free inside the swollen
stalk, whereas in the pear and apple the entire fruit grows into a
single solid mass. Here also, as before, we can trace a gradual
development from the bushy to the tree-like form.

[Illustration: images/i221.jpg]

Fig. 47.--Vertical section of Apple-blossom.

The common hawthorn of our hedges shows us, perhaps, the simplest stage
in the evolution of the apple tribe. It grows only into a tall bush, not
unlike that of the blackthorn, and similarly armed with stout spines,
which are really short sharp branches, not mere prickly hairs, as in the
case of the brambles. Occasionally, however, some of the hawthorns
develop into real trees, with a single stumpy trunk, though they never
grow to more than mere small spreading specimens of the arboreal type,
quite unlike the very tall and stately pear-tree. The flowers of the
hawthorn--may-blossom, as we generally call them--are still essentially
of the rose type; but, instead of having a single embryo seed and simple
fruit in the centre, they have a compound fruit, inclosing many seeds,
and all embedded in the thick fleshy calyx or flower-cup. As the haw
ripens the flower-cup outside grows redder and juicier, and the seed
pieces at the same time become hard and bony. For it is a general
principle of all edible fruits that, while they are young and the seeds
are unripe, they remain green and sour, because then they could only be
losers if eaten by birds; but as the seeds ripen and become fit to
germinate, the pulp grows soft and sweet, and the skin assumes its
bright hue, because then the birds will be of service to it by diffusing
the mature seeds. How largely birds assist in thus dispersing plants has
very lately been proved in Australia, where a new and troublesome weed
has rapidly overrun the whole country, because the fruit-eaters are very
fond of it, and scatter its seeds broadcast over the length and breadth
of the land.

The common medlar is nothing more than a hawthorn with a very big
overgrown haw. In the wild state it bristles with hard thorns, which are
wanting to the cultivated form, and its flower almost exactly resembles
that of the may. The fruit, however, only becomes edible after it begins
to decay, and the bony covering of the seeds is remarkably hard. It
seems probable that the medlar, originally a native of southern Europe,
is largely dispersed, not by birds, but by mice, rats, and other small
quadrupeds. The colour is not particularly attractive, nor is the fruit
particularly tempting while it remains upon the bush; but when it falls
upon the ground and begins to rot, it may easily be eaten by rodents or
pigs, and thus doubtless it procures the dispersion of its seeds under
conditions highly favourable to their proper growth and success in life.

The little Siberian crabs, largely cultivated for their fruit in
America, and sometimes found in English shrubberies as well, give us one
of the earliest and simplest forms of the real apple group. In some
respects, indeed, the apples are even simpler than the hawthorn, because
their seeds or pips are not inclosed in bony cases, but only in those
rather tough leathery coverings which form what we call the core. The
haw of the hawthorn may be regarded as a very small crab-apple, in which
the walls of the seed cells have become very hard and stony; or the crab
may be regarded as a rather large haw, in which the cell walls still
remain only thinly cartilaginous. The flowers of all the group are
practically identical, except in size, and the only real difference of
structure between them is in the degree of hardness attained by the seed
covers. The crabs, the apples, and the pears, however, all grow into
tallish trees, and so have no need for thorns or prickles, because they
are not exposed to the attacks of herbivorous animals. Ordinary orchard
apples are, of course, merely cultivated varieties of the common wild
crabs. In shape the apple-tree is always spreading, like an arboreal
hawthorn, only on a larger scale. The pear-tree differs from it in two
or three small points, of which the chief are its taller and more
pyramidal form, and the curious tapering outline of the fruit.
Nevertheless, pear-trees may be found of every size and type, especially
in the wild state, from a mere straggling bush, no bigger than a
hawthorn, to a handsome towering trunk, not unlike an elm or an alder.

In the matter of fruits, the apple group are more advanced than the
roses, but so far as regards the flower alone, viewed as an organ for
attracting insects, many of the apple tribe are inferior to the true
roses. Here again, however, we can trace a regular gradation from the
small white blossoms of the may, through the larger blushing pink
flowers of the apple, to the very expanded and brilliant crimson petals
of that beautiful ornamental species of pear, the Pyrus japonica, so
often trained on the sunny walls of cottages.

The quince is another form of apple very little removed from its
congeners except in the fruit. More different in external appearance is
the mountain-ash or rowan-tree, which few people would take at first
sight for a rose at all. Nevertheless, its flowers exactly resemble
apple-blossom, and its pretty red berries are only small crabs, dwarfed,
no doubt, by its love for mountain heights and bleak windy situations,
and clustered closely together into large drooping bundles. For the same
reason, perhaps, its leaves have been split up into numerous small
leaflets, which causes it to have been popularly regarded as a sort of
ash. In the extreme north, the rowan shrinks to the condition of a
stunted shrub; but in deep rich soils and warmer situations it rises
into a pretty and graceful tree. The berries are eagerly eaten by birds,
for whose attraction most probably they have developed their beautiful
scarlet colour.

So far, all the members of the rose family with which we have dealt have
exhibited a progressive advance upon the common simple type, whose
embodiment we found in the little wayside potentillas. Their flowers,
their fruits, their stems, their branches, have all shown a regular and
steady improvement, a constant increase in adaptation to the visits of
insects or birds, and to the necessities for defence and protection. I
should be giving a false conception of evolution in the roses, however,
if I did not briefly illustrate the opposite fact of retrogressive
development or degeneration which is found in some members of the class;
and though these members are therefore almost necessarily less familiar
to us, because their flowers and fruits are inconspicuous, while their
stems are for the most part mere trailing creepers, I must find room to
say a few words about two or three of the most noteworthy cases, in
order to complete our hasty review of the commonest rosaceous tribes.
For, as we all know, development is not always all upward. Among plants
and animals there are usually some which fall behind in the race, and
which manage nevertheless to eke out a livelihood for themselves in some
less honourable and distinguished position than their ancestors. About
these black sheep of the rose family I must finally say a few words.

In order to get at them, we must go back once more to that simple
central group of roses which includes the potentillas and the
strawberry. These plants, as we saw, are mostly small trailers or
creepers among grass or on banks; and they have little yellow or white
blossoms, fertilised by the aid of insects. In most cases their flowers,
though small, are distinct enough to attract attention in solitary
arrangement. There are some species of this group, however, in which the
flowers have become very much dwarfed, so that by themselves they would
be quite too tiny to allure the eyes of bees or butterflies. This is the
case among the meadow-sweets, to which branch also the spiræas of our
gardens and conservatories belong. Our common English meadow-sweet has
close trusses of numerous small whitish or cream-coloured flowers,
thickly clustered together in dense bunches at the end of the stems; and
in this way, as well as by their powerful perfume, the tiny blossoms,
too minute to attract attention separately, are able to secure the
desired attentions of any passing insect. In their case, as elsewhere,
union is strength. The foreign spiræas cultivated in our hothouses have
even smaller separate flowers, but gathered into pretty, spiky antler-
like branches, which contrast admirably with the dark green of the
foliage, and so attain the requisite degree of conspicuousness. This
habit of clustering the blossoms which are individually dwarfed and
stunted may be looked upon as the first stage of degradation in the
roses. The seeds of the meadow-sweet are very minute, dry, and inedible.
They show no special adaptation to any particular mode of advanced
dispersion, but trust merely to chance as they drop from the dry capsule
upon the ground beneath.

[Illustration: images/i229.jpg]

Fig. 48.--Single flower of Salad Burnet, male and female.

A far deeper stage of degradation is exhibited by the little salad-
burnet of our meadows, which has lost the bright petals of its flowers
altogether, and has taken to the wasteful and degenerate habit of
fertilisation by means of the wind. We can understand the salad-burnet
better if we look first at common agrimony, another little field weed
about a foot high, with which most country people are familiar; for,
though agrimony is not itself an example of degradation, its arrangement
leads us on gradually to the lower types. It has a number of small
yellow flowers like those of the cinquefoil; only, instead of standing
singly on separate flower stalks, they are all arranged together on a
common terminal spike, in the same way as in a hyacinth or a gladiolus.
Now, agrimony is fertilised by insects, and therefore, like most other
small field roses, it has conspicuous yellow petals to attract its
winged allies. But the salad-burnet, starting from a somewhat similar
form, has undergone a good deal of degradation in adapting itself to
wind-fertilisation. It has a long spike of flowers, like the agrimony;
but these flowers are very small, and are closely crowded together into
a sort of little mop-head at the end of the stem. They have lost their
petals, because these were no longer needed to allure bees or
butterflies, and they retain only the green calyx or flower-cup, so that
the whole spike looks merely a bit of greenish vegetation, and would
never be taken for a blossoming head by any save a botanical eye. The
stamens hang out on long thread-like stems from the cup, so that the
wind may catch the pollen and waft it to a neighbouring head; while the
pistils which it is to fertilise have their sensitive surface divided
into numerous little plumes or brushes, so as readily to catch any stray
pollen grain which may happen to pass their way. Moreover, in each head,
all the upper flowers have pistils and embryo seed vessels only, without
any stamens; while all the lower flowers have stamens and pollen bags
only, without any pistils. This sort of division of labour, together
with the same arrangement of seed-bearing blossoms above and pollen-
bearing blossoms below, is very common among wind-fertilised plants, and
for a very good reason. If the stamens and pistils were inclosed in a
single flower they would fertilise themselves, and so lose all the
benefit which plants derive from a cross, with its consequent infusion
of fresh blood. If, again, the stamens were above and the pistils below,
the pollen from the stamens would fall upon and impregnate the pistils,
thus fertilising each blossom from others on the same plant--a plan
which is hardly better than that of self-fertilisation. But when the
stamens are below and the pistils above, then each flower must
necessarily be fertilised by pollen from another plant, which ensures in
the highest degree the benefits to be derived from a cross.

Thus we see that the salad-burnet has adapted itself perfectly to its
new mode of life. Yet that adaptation is itself of the nature of a
degradation, because it is a lapse from a higher to a lower grade of
organisation--it is like a civilised man taking to a Robinson Crusoe
existence, and dressing in fresh skins. Indeed, so largely has the
salad-burnet lost the distinctive features of its relatives, the true
roses, that no one but a skilled botanist would ever have guessed it to
be a rose at all. In outer appearance it is much more like the little
flat grassy plantains which grow as weeds by every roadside; and it is
only a minute consideration of its structure and analogies which can
lead us to recognise it as really and essentially a very degenerate and
inconspicuous rose. Yet its ancestors must once have been true roses,
for all that, with coloured petals and all the rosaceous
characteristics, since it still retains many traces of its old habits
even in its modern degraded form.

[Illustration: images/i232.jpg]

Fig. 49.--Flower of Stanch-Wound or Great Burnet.

We have in England another common weed, very like the salad-burnet, and
popularly known as stanch-wound, or great-burnet, whose history is quite
as interesting as that of its neighbour. The stanch-wound is really a
salad-burnet which has again lost its habit of depending upon the wind
for fertilisation, and has reverted to the earlier insect-attracting
tactics of the race. As it had already lost its petals, however, it
could not easily replace them, so it has coloured its calyx or flower-
cup instead, which answers exactly the same purpose. In other words,
having no petals, it has been obliged to pour the purple pigment with
which it allures its butterfly friends into the part answering to the
green covering of the salad-burnet. It has a head of small coloured
blossoms, extremely like those of the sister species in many respects,
only purple instead of green. Moreover, to suit its new habits, it has
its cup much more tubular than that of the salad-burnet; its stamens do
not hang out to the wind, but are inclosed within the tube; and the
pistil has its sensitive surface shortened into a little sticky knob
instead of being split up into a number of long fringes or plumes. All
these peculiarities of course depend upon its return from the new and
bad habit of wind-fertilisation to the older and more economical plan of
getting the pollen carried from head to head by bees or butterflies. The
two flowers grow also exactly where we should expect them to do. The
salad-burnet loves dry and wind-swept pastures or rocky hill-sides,
where it has free elbow-room to shed its pollen to the breeze; the
stanch-wound takes rather to moist and rich meadows, where many insects
are always to be found flitting about from blossom to blossom of the
honey-bearing daisies or the sweet-scented clover.

Perhaps it may be asked, How do I know that the salad-burnet is not
descended from the stanch-wound, rather than the stanch-wound from the
salad-burnet? At first sight this might seem the simpler explanation of
the facts, but I merely mention it to show briefly what are the sort of
grounds on which such questions must be decided. The stanch-wound is
certainly a later development than the salad-burnet; and for this reason
--it has only four stamens, while the parent plant has several, like all
the other roses. Now, it would be almost impossible for the flower first
to lose the numerous stamens of the ordinary rose type, and then to
regain them anew as occasion demanded. It is easy enough to lose any
part or organ, but it is a very different thing to develop it over
again. Thus the great-burnet, having once lost its petals, has never
recovered them, but has been obliged to colour its calyx instead. It is
much more natural, therefore, to suppose that the stanch-wound, with its
few stamens and its clumsy device of a coloured calyx instead of petals,
is descended from the salad-burnet, than that the pedigree should run
the other way; and there are many minor considerations which tend in the
same direction. Most correctly of all, we ought perhaps to say that the
one form is probably a descendant of ancestors more or less like the
other, but that it has lost its ancestors' acquired habits of wind-
fertilisation, and reverted to the older methods of the whole tribe.
Still, it has not been able to replace the lost petals.

I ought likewise to add that there are yet other roses even more
degenerate than the burnets, such as the little creeping parsley-piert,
a mere low moss-like plant, clinging in the crannies of limestone rocks
or growing on the top of earthy walls, with tiny green petalless
flowers, so small that they can hardly be distinguished with the naked
eye. These, however, I cannot now find space to describe at length; and,
indeed, they are of little interest to anybody save the professional
botanist. But I must just take room to mention that if I had employed
exotic examples as well as the familiar English ones, I might have
traced the lines of descent in some cases far more fully. It is perhaps
better, however, to confine our attention to fairly well-known plants,
whose peculiarities we can all carry easily in our mind's eye, rather
than to overload the question with technical details about unknown or
unfamiliar species, whose names convey no notion at all to an English
reader. When we consider, too, that the roses form only one family out
of the ninety families of flowering plants to be found in England alone,
it will be clear that such a genealogy as that which I have here
endeavoured roughly to sketch out is but one among many interesting
plant pedigrees which might be easily constructed on evolutionary
principles. Indeed, the roses are a comparatively small group by the
side of many others, such as the pea-flowers, the carrot tribe, and the
dead-nettles. Thus, we have in England only forty-five species of roses,
as against over two hundred species of the daisy family. Nevertheless, I
have chosen the rose tribe as the best example of a genealogical study
of plants, because most probably a larger number of roses are known to
unbotanical readers than is the case with any other similar division of
the vegetable world.

* * *

## VIII.

### _CUCKOO-PINT._[10]

[Illustration: images/i237.jpg]

Fig. 50.--Cuckoo-Pint (Arum Maculatum).

Close by the hedge-side there runs a little streamlet known to the
village children for two miles around by the strangely pleonastic title
of the Bourne Brook. Pleonastic, I say, because bourne is, of course,
good old English for what in modern English we call a brook, so that the
two halves of the common name are, in fact, synonymous, the later word
being added to the earlier by the same sort of unconscious reduplication
as that which gives us the double forms of Windermere Lake or Mount Ben
Jerlaw. I can't tell you, though, what a world of life and interest is
to be found among the low cliff banks and tiny shingle patches that
bound the Bourne Brook. In the stream itself there are darting crayfish,
which we can catch with our fingers by lifting up the green slimy
stones; there are caddis-worms, and big pond snails, and pouting
miller's thumbs, and iridescent stickleback; it is even rumoured, though
I doubt whether on sufficient authority, that there are actually and
positively in some of its pools and stickles genuine unadulterated real
live trout. I know as a fact, however, that there are freshwater
mussels, for these I have fished up with my little dredging-net, and
safely domesticated in the bell-glass aquarium. In the fields around
there are ferns, and marsh-marigolds, and rushes, and roast-beef plants.
And beside the water's edge there are abundant leaves and blossoms of
that strange flower the cuckoo-pint, whose counterfeit presentment you
see in the figure on the previous page. Now, cuckoo-pint, or lords-and-
ladies, or wild arum, whichever you choose to call it, is a very
singular plant indeed; and it seems to me we cannot do better than sit
down and dissect one for the sake of understanding its queer internal
arrangements. If it were a newly discovered Central African lily, we
should all be reading about its extraordinary adaptations in all the
newspapers: much more then, since it is a common English plant we have
all known familiarly from childhood upward, ought we to wish for some
explanation of its singular shape and its wonderful devices for
entrapping and intoxicating helpless little flying insects.

First of all, we must begin by recognising that the apparent flower of
the cuckoo-pint is not one single blossom, but a whole group of separate
blossoms, closely crowded together in two or three little distinct
bundles on a long spike or succulent stem. And in order to let us all
clearly understand the meaning and nature of the entire compound
structure, I think we had better divide our subject (as if it were a
sermon) into three heads. First, we must consider what are the actual
parts to be distinguished from one another in the flower of the cuckoo-
pint at the present day. Secondly, we must ask what was the course of
evolution by which they each assumed those peculiar forms. And thirdly,
we must inquire what good purpose in the economy of the plant is
subserved by each part in the existing cuckoo-pints as we now find them.
We shall thus have learnt, at last, what a cuckoo-pint is, how it came
to be so, and why its various portions have been brought to assume their
present forms.

[Illustration: images/i239.jpg]

Fig. 51.

Spadix of Arum.

Beginning, then, with the purely structural or positive arrangement of
the cuckoo-pint as we find it in nature at the present day, we see at
once that its blossom consists mainly of a large greenish-purple sheath
or hood, at the top of a long stalk, inclosing a tall fleshy spike or
club, shaped something like a mace, and protruding from the hood in
front, so as to show its coloured and expanded summit above the point of
junction of the two lips. That is all that one can see of the blossom
from the outside; but in reality these two conspicuous organs form no
part of the actual and genuine flowers themselves at all. They are
merely incidental accessories, put there for an excellent purpose
indeed, as everything always is in the balanced economy of nature; but
not essential or necessary to the existence of the flowers as flowers,
though most noticeable from their size and hue to the superficial eyes
of the unscientific human kind. In order to see the true flowers
themselves, we must cut open the side of the hood or sheath, as has been
done in the accompanying diagram, and then one can observe a number of
small knobby bodies clustering in three groups along the lower part of
the club-shaped spike or central axis. Those little knobby bodies, of
which there are a great many in each arum, form the real blossoms of the
cuckoo-pint; and they are inclosed in the sheathing hood for a very good
reason, as we shall hereafter see, in order to ensure the carrying out
of their proper function, the final production of seeds and berries.

If one looks closely at the diagram, however, one can notice that these
little knobby flowers are not all quite similar to one another. They
consist of three distinct kinds, all three of which are always found in
true arums of this type. At the bottom there are a whole group of small
cushion-like green lumps, each with a little point in its centre, and
all closely packed together in several irregular rows, like Indian corn
on the cob. These green lumps are the pistil-bearing flowers; each of
them represents a single very degraded blossom, and each will grow out
at a later stage into one of the bright scarlet berries which form such
beautiful objects in the hedgerow and waysides during the autumn months.
We could not possibly have a simpler type of flower than these lowest
pistil-bearing blossoms; they are in fact the central floral notion
reduced to its ideally simplest terms. They consist each of a single
rudimentary berry, containing a single seed, and crowned by a little
point or stigma, which is the sensitive surface to be fertilised by the
pollen from the other flowers.

In the middle, here, come the flowers of this second or pollen-bearing
sort, each of which again consists of naked stamens; that is to say,
each flower is here reduced to one solitary part, analogous to the
little pollen-sacs that you see hanging out in the centre of a tiger
lily or most other conspicuous garden blossoms. Every such stamen is
made up of two tiny bags, which open when ripe and discharge their
golden pollen. Though the pollen looks to the naked eye like mere yellow
dust, yet, when put under a microscope, it is seen to consist of small
egg-like bodies, having a characteristic shape and appearance in each
different flower, exactly as the seeds and fruits have to the naked eye.
With these two essential elements of floral architecture we are now
pretty familiar from our previous examination of other plants.

On top of all, however, come a group of very peculiar blossoms, found
only in the arum and nowhere else, and consisting of several little
green knobs, like those of the pistil-bearing flowers, but each crowned
by a long hair or filament, bent downwards towards the base of the hood
or sheath, and very much larger than the sensitive surface of the lower
blossoms. The origin and meaning of these peculiar organs we will come
to consider later on: for the present it will be sufficient to observe
their shape and position, and to notice that their hairs point downward
and inward like the spikes of a lobster pot, at a point exactly
corresponding to the narrowest neck or throat of the inclosing sheath.

And now, how did the cuckoo-pint come to possess this very singular
arrangement of tiny separate flowers in a close spike, female below,
male in the centre, and neuter or rudimentary on the top of all? To
answer this question properly, we must go back to the earlier ancestors
of the arum tribe--and I may as well start fair by saying at once that
the arums are by descent degenerate lilies, like wheat, and that each of
these very degraded little flowers really represents a primitive full-
blown and bright-coloured lily blossom. You will remember that a true
lily is made up of six brilliant petals or flower-leaves, inclosing six
long pendulous stamens, and with a seed-vessel or ovary of three cells
in the very centre. Such a blossom as that we call a perfect flower,
because it possesses within itself all the component elements of any
blossom--calyx, petals, stamens, and pistil. Moreover, it is, so to
speak, a self-contained and self-sufficing flower; it has bright petals
to entice an insect fertiliser, pollen to impregnate its ovary, and
embryo seeds to form the future ripe fruit. But as we have so often
noticed, it is highly undesirable for a flower to be fertilised with
pollen from its own stamens: those plants which are impregnated from the
stamens of their neighbours always produce more seed and stronger
seedlings than those which are impregnated with home-made pollen from
their own sacs. Hence, cross-fertilisation, we know, is the great end
aimed at by all flowers; and those plants which happen to vary in any
direction favourable to cross fertilisation invariably succeed best in
the struggle for life, while those which happen to vary in any direction
hostile to it, or which acquire the bad habit of self-fertilisation,
tend slowly to go to the wall and to die out from inherited and ever-
increasing feebleness of constitution.

There can be very little doubt that the ancestors of the arums had
originally six coloured petals like the lilies, for a reason which I
will shortly mention; and inside these petals were six stamens and a
three-celled ovary or unripe capsule. It is a very long step, certainly,
from such perfect flowers as those to such very rudimentary and reduced
types as the little florets which we get in the cuckoo-pint, each
consisting of a few stamens or a single one-seeded fruitlet, without any
trace of petals whatsoever. Yet we have very good evidence of the slow
course of degradation by which the arums have reached their present
condition; and, as happened in the case of wheat, several surviving
intermediate forms enable us to bridge over the intervening gulf. In
other words, there are plants which resemble the lilies in some things,
while they resemble the arums in others; and by means of these plants we
can trace a regular gradation from the perfect and bright-coloured
flowers of the true lily to the imperfect and inconspicuous little
unisexual blossoms of our English cuckoo-pint. It is interesting, too,
to observe how the very same original stock which in one direction gave
birth to the degenerate wind-fertilised wheat and grasses, has in
another direction given birth to the equally degenerate but insect-
fertilised arums and their congeners. The one case shows the course of
degradation as it takes place in poor dry soils; the other case shows it
as it takes place in the moist and rich mould of watery ditches.

[Illustration: images/i245.jpg]

Fig. 52.--Single flower of Sweet-sedge.

Look first at the curious flower which is represented for us here in the
little sketch at the side. In the slow rivers of Suffolk, and along the
shallow edges of the Norfolk broads, there grows a pretty spiky water-
plant, known by the scientific name of Acorus, or by the simpler English
titles of sweet-flag and sweet-sedge. This acorus is a highly aromatic
reed-like plant, with long lance-shaped leaves, and a dense spike of
small yellowish-green blossoms, standing out in a cylindrical form from
the thick rod which does duty for its stem. At first sight you would not
say that these flowers differed very much from those of the arum: they
look pretty much the same sort of small unnoticeable green knobs to a
casual observer. But when one comes to pick out one of them from the
close mass, and to examine it with a common pocket lens, one can see at
once that, though very much reduced in size and colour, it is still at
bottom essentially a lily flower. In the diagram we have one of these
small blossoms considerably enlarged, and it is easy to see that it
possesses all the various parts which characterise the true lilies.
There are six petals, clearly enough, though they are minute and green
instead of being brilliantly coloured; and they are closely folded over
the central organs, instead of being bent back and displayed
ostentatiously to the eyes of passing insects. There are six stamens
too, one under each petal, almost concealed by the scale-like covering;
and in the centre there is an ovary which when cut across proves to have
sometimes two and sometimes three seed-bearing cells, for the number
here has become a little indefinite: nature, as so often happens, has
begun to lose count. There can be no sort of doubt, then, that acorus
represents a very reduced and degraded lily, still retaining all its
primitive structural arrangements, but with its flowers greatly
diminished in size, and with its original bright colour almost entirely
lost by disuse and degradation.

The reason why this little acorus or sweet-sedge has thus gone backward
in the course of development is not a very difficult one to understand.
Brilliant flowers like the lilies depend for fertilisation upon large
colour-loving insects, such as bees and butterflies, which are attracted
by their flaunting hues and their abundant store of rich honey, and so
unconsciously carry the impregnating pollen from head to head. But many
other plants find it suits their purpose better to depend either upon
the wind or upon small insect friends of less pronounced æsthetic
tastes; and this is especially the case, among other classes, with
almost all waterside plants. Hence such plants have usually acquired
small and inconspicuous separate flowers; and then, to make up for their
loss in attractiveness, like cheap sweetmeats, they have very largely
increased their numbers. Or, to put the matter more simply and
physically, in waterside situations those plants succeed best which have
a relatively large number of individually small and unnoticeable
flowers, massed together into large and closely serried bundles. Hence,
in such situations, there is a tendency for petals to be suppressed, and
for blossoms to grow minute; because the large and bright flowers seldom
succeed in attracting big land-insects like bees or butterflies, while
the small and thick-set ones usually do succeed in attracting a great
many little flitting waterside midges. Examples may be found in the
rushes, bur-reeds, catstails, and many other freshwater plants.

For such a _rôle_ our friend the sweet-sedge is peculiarly well adapted.
Its small yellowish blossoms, though separately unnoteworthy, are
rendered conspicuous in the mass by their dense grouping: and its
extremely aromatic perfume makes it a great favourite with the tiny
flies and water-haunting insects, who are much more guided in their
search for food by scent than by sight. These little flies carry its
pollen from one head to another, and so unconsciously fertilise the
future seeds, and give the plant a firm foothold in all situations which
are naturally suitable for its peculiar mode of growth.

[Illustration: images/i248.jpg]

Fig. 53.--Single flower of

Marsh Calla.

The common marsh calla of northern Europe (fig. 53) bridges over the gap
between this English plant and the stages below it on the path of
degradation. Calla has by disuse quite lost its petals, but it
nevertheless retains six stamens to each flower, grouped round a single
ovary. Here the close relationship to the true lilies still remains
quite apparent.

Next in descending order, on the way to the cuckoo-pint, we may take
that common white lily which grows so often in cottage windows, and
which boasts more names, Latin and English, than almost any other plant
whose personal acquaintance I have ever had the pleasure of making. The
members of a Sheffield long firm themselves have seldom so many aliases
as this honest and unoffending flower. Botanists call it Richardia
Africana; gardeners dub it Calla Æthiopica; and the general public knows
it indiscriminately as Æthiopian lily, white calla, snowy arum, St.
Helena arrowroot, and lily of the Nile. However, in spite of its
numerous disguises, I dare say it will be easy to recognise the plant I
mean, when I say that it is very much like a cuckoo-pint, only with a
pure snow-white hood, and a bright golden yellow spike projecting from
the top. As in the cuckoo-pint this golden spike is the part which
contains the true flowers; and the snow-white hood is only a sort of
shroud or cloak which covers them in from the vulgar gaze. The Æthiopian
lily, then (since we _must_ choose one among its many names), presents
us with a further step on the downward path of degradation from the true
lilies towards the thoroughgoing cuckoo-pint: for, as preachers justly
remark, there is no drawing a line after you have once begun upon the
wrong track, and a lily which lets in the thin end of the wedge by
becoming a sweet-sedge is almost certain to end at last, in the form of
its remote descendants, as a mere degenerate and neglected arum.

When we cut open the hood of the Æthiopian lily, we find inside it a
spike somewhat resembling that of the cuckoo-pint, but differing in one
or two important particulars. Near the bottom, at a point corresponding
to that where the female flowers grow in the wild English arum, the
white Æthiopian lily has a number of small greenish knobs, apparently
embedded in a golden yellow matrix; at the top, the whole of the spike
consists of a similar golden-yellow substance, which, at a certain
period in the flowering process, effloresces, so to speak, with a
copious greasy white dust, something like starch or wheaten flour. But
if we split down the spike itself through the centre, we can soon find
out what is the meaning of this curious arrangement. The golden
substance which makes up the mass of the spike consists really of
innumerable yellow stamens, packed so tightly together over the whole
stem, and so closely sessile (as we call it technically) upon the
central axis, that they look like a single piece of homogeneous waxy
material. You can separate them from one another, however, with your
fingers, and then you see that each one is roughly pentagonal or
hexagonal in outline, owing to the pressure of its surrounding
neighbours, and that it consists essentially of a small pollen bag,
containing a quantity of yellowish liquid. When the stamens are quite
ripe, this liquid assumes the form of small white pollen grains, which
are pushed out as the bags open, and become the efflorescence or powder
that covers the spike in its ripe state. At the bottom of the spike,
where we get the pistil-bearing flowers in the cuckoo-pint, the
Æthiopian lily has several small blossoms intermediate between the
perfect flowers of the acorus, or the half-perfect flowers of the marsh
calla, and the very imperfect flowers of the arum; for each of them has
here a central green knob or capsule, surrounded irregularly by four or
five stamens, but without any petals, or even any scales to represent
them. These form the green bodies which I have already described as
apparently embedded in a hard yellow matrix; and that yellow matrix is
composed of the stamens. The lower part of the Æthiopian lily, in fact,
consists of irregular flowers which, like those of the marsh calla, have
quite lost their petals, but which still retain an indefinite number of
stamens grouped around a single pistil; while in the upper part, as in
the central group of the arum, the pistils have disappeared also, and
only the stamens remain. Such a plant as this lily, then, is clearly on
the way to becoming what the arum has actually become: its flowers
already show a tendency toward the unisexual condition. In the upper
portion they have all become actually unisexual, for there we get
nothing but stamens; in the lower part they remain irregularly bisexual,
for there, though the stamens are often reduced in number--nature losing
count again--some of them still remain embedded on the spike between the
scattered pistils. This result is just what you might naturally expect
from squeezing a lot of marsh calla blossoms closely together on a
spike. Even in the upper half of the spike, the blossoms often keep up
some marks of their original bisexual character, for you will
occasionally find a few stray green knobs sparsely sprinkled here and
there among the golden stamens of the top portion. Nevertheless, we may
fairly say that even here a tendency towards specialisation has been
distinctly set up: the uppermost flowers tend to become almost entirely
pollen bearing sacs, and the lowermost flowers tend to become
preponderatingly, though not entirely, seed-bearing ovaries.

Now if we turn from these transitional steps to the completely developed
arum, what do we find? Here, the top of the spike has become absolutely
bald and bare of flowers, instead of being covered, as in the Æthiopian
lily, with thickly grouped florets up to its very summit; and at the
same time, the actual flowers in the lower portion, instead of running
together into an uninterrupted cone, are separated into three distinct
groups or bodies. At the bottom of all, as in the Æthiopian lily, we now
get the female flowers alone; only, instead of being intermixed with
stamens, they consist simply of naked ovaries; the differentiation or
specialisation of the flowers is here complete. Above them, as before,
we get the male flowers, reduced to a single stamen, or rather to a
group of from four to six stamens each, all run together: for though it
is usual to consider each stamen as a separate flower (which it
certainly is in some still more degraded arums, like the little
'Capuchin' of southern Europe), I think the analogy of marsh calla and
the Æthiopian lily justifies us in regarding them as groups of six, more
or less defective, and jammed closely together, with the ovaries crushed
out between them. And at the top of all we get a perfectly new factor in
the compound community--a number of green sacs capped by downward-
pointing hairs, which are, in fact, abortive pistils, like those organs
that form the lower group, only with their ovaries barren, and their
styles or sensitive surfaces lengthened out into spiky hairs.[11] What
may be the use or function of these curious objects we will proceed to
inquire a little later: for the present we must turn our attention to
the origin of another part of the cuckoo-pint's apparent blossom, the
large and conspicuous greenish-purple hood, which alone composes the
flower in the popular sense of the word.

There is nothing at all like that, a casual observer would probably be
tempted at first to say, in any ordinary true lily that any one ever yet
came across. A bunch of lilies growing on a stalk, with a sort of huge
winding-sheet wrapped round them, is a thing that surely nobody has ever
seen. So it would seem at a first glance; and yet there is one lily-like
plant that we all know well, in which the flowers are at one time
wrapped up in exactly such an enveloping sheet. Have you ever watched a
narcissus or a daffodil unfolding its pretty yellow buds? If you have,
you will remember that at first they are all tightly covered over by a
thin papery membrane, shaped exactly like the hood of this cuckoo-pint;
and that after the scented blossoms have all come out, this membrane, or
spathe, as we call it in the horrid technical language of botany, turns
back upon the stem, like a sort of cup below the flowers. To be sure,
the daffodil and the narcissus are not, in the strictest sense of the
word, true lilies at all, but amaryllids, because they have got an
inferior instead of a superior ovary; but, even in the technically
restricted lily family itself, there are lilies with just such a spathe
or enveloping membrane, as in the familiar head of onions and garlic, as
well as in some more respectable and dignified flowers. Now, one has
only got to suppose the number of buds in each head largely increased,
the whole head lengthened out into a spike, and the spathe or sheath
grown larger into a completely inclosing hood, and there we have at once
an arum or an Æthiopian lily. Only, as often happens under such
circumstances, the individual flowers have now grown too small to
attract the fertilising insects separately on their own account; so the
spathe or hood has to do duty for them all at once collectively. It
incloses and conceals the various minute flowers, but it becomes itself
coloured and attractive, so as to allure the eyes of the little insects
on behalf of the entire community. In other words, when the central
flowers had become so much diminished in size by disuse, by loss of
their petals, and by specialisation of sexes, they ran no chance of
getting fertilised at all unless they possessed some exceptional means
of attracting insects. Hence those alone have survived which happened to
develop some such attractive organ as the hood of the Æthiopian lily or
the purple central spike of the English arum.

And now we come at last to the final purpose of all these curious
structural arrangements. The object of them all is of course to ensure
the cross-fertilisation of the different heads of flowers; but the
special way in which they effect this universal end is singularly
ingenious, interesting, and almost intentional in its design. The
Æthiopian lily, one can readily understand, attracts many insects by its
large brilliant white hood, as well as by the rich golden-yellow colour
of the stamens which cover the summit of its spike. But in the arum the
top of the spike is bare, and has become expanded into a club-shaped
organ, which is deeply tinged with purple, and stands out vividly
against the bright green of the spathe at its back, so as to form an
excellent advertisement for the giddy eyes of little passing winged
insects. It is upon these insects that the arum depends entirely for
fertilisation, and the way in which it manages to obtain their services
is as curious as anything in the whole range of vegetable existence.

If, when the arum-flowers are just beginning to blossom, I were to cut
down one of the hoods halfway through the centre, sideways, I should
find a great many tiny winged flies all crawling about at the very
bottom of the deep tube. They have come from some other neighbouring
arum-flower, where they have been well dusted with the golden pollen;
and they crawl down the neck of the hood, past the lobster pot hairs
which close its narrowest portion, into the broader open space beneath.
Here they find the pistil-bearing blossoms just ripe for impregnation;
and, crawling over them in an aimless sort of fashion, they rub off upon
their sensitive surfaces some of the pollen which they brought with them
from the last plant they visited. This pollen thus cross-fertilises the
fruit, and produces in it seeds which are the product of two distinct
parents, and therefore capable of springing up into vigorous seedlings
of the strongest sort.

But though the small flies have thus benefited the plant by fertilising
its ovaries with pollen brought from another head, they have as yet got
no return for their trouble in the shape of meat or drink: and, unless
they did so, they certainly would not take the trouble to visit any
other flower of the same sort. The stamens are not yet ripe, and do not
ripen until after the pistils have set their fruit. If they did
otherwise, then the pollen would fall from them down upon the sensitive
surfaces of their sister blossoms below, and the plant would accordingly
be self-fertilised--a thing to be always avoided as far as possible.
Accordingly, it is a fixed rule in the cuckoo-pints that the pistils,
which are below, come to maturity first, while the stamens, which are
above, shed their stock of pollen a day or two later. This being so, the
flies find nothing in the new flower to detain them any longer; and, if
they could, they would crawl up the spike and get out again by the same
way as they got in, never troubling themselves any more about such
useless flowers. Here, however, the curious lobster-pot hairs for the
first time come into play. They act, in short, exactly like a common
eel-trap. The flies walked in easily enough, the way the hairs naturally
pointed; but when they try to walk out again, they find their way
completely blocked by the chevaux-de-frise of stiff bristles. There is
nothing that beats a crawling insect like a thicket of hairs; he finds
it as impossible to creep up against their grain as we ourselves find it
to force our way through a tropical jungle of cactus and prickly
spurges. So there they wait perforce for a time in durance vile,
wandering up and down helplessly among the lower flowers, and
effectually brushing off against them every single grain of pollen which
they brought on their legs or breasts from the last flower they visited.

At last, in a day or so, the young berries begin to swell slowly, and
all the pistil-bearing flowers show by this quickening action that they
have been duly and properly fertilised. Then comes the turn of the
stamens. One after another they open their little double pollen-sacs,
and shed their golden powder down upon the wings and bodies of the small
flies imprisoned beneath. Even if a little of it happens to catch upon
the pistils here and there, that does not matter now, for all the
ovaries are already duly impregnated, and the sensitive surfaces have
shrivelled utterly away; so most of the pollen falls on to the floor of
the hood, where the small flies are waiting impatiently and hungrily for
the Danae flood. It covers them all over from head to foot with the
golden grains, and clogs their legs and wings and bodies in every
portion. A fine time the flies have of it then. They get actually drunk
with pollen after their fast; and, if you cut open one of the hoods in
this stage of development, you will find the little creatures positively
reeling about in their intoxication, and so full-fed with rich grains
that they can hardly use their legs or wings to crawl or fly. A little
fresh air seems to revive them slightly, as is often the case with other
gentlemen under similar circumstances; and then they can feebly fly away
after a few minutes.

But in the natural state of things, when no wandering botanist comes
with his penknife to make what he calls in his lively language a
'longitudinal section of Arum maculatum,' the flies remain at the bottom
of their deep well till they have eaten almost all the pollen, and got
most helplessly and stupidly drunk in the process. A great waste of
pollen this, for the plant, of course; but still it costs no more than
honey would do, and quite enough remains on the legs and wings of the
flies to impregnate their fellow-blossoms on another plant. At last all
the pollen is shed and eaten, and then the flies again become anxious to
shift their quarters to some more favourable spot, where there is more
food to be found, and another drunken orgy to be expected. This time,
however, the hairs no longer impede their progress; they have all
shrivelled up meanwhile, and the eel-trap is therefore now dissolved; so
the flies hurry away once more, covered with the stock of pollen-dust
which has been showered down upon them by their late host.

One might suppose, at first, that after one such experience the flies
would studiously avoid cuckoo-pints in future. Nothing of the sort.
Experience seems to be thrown away upon insects; and besides, the little
creatures seem actually to enjoy their intoxicated revels. Pollen
apparently acts upon them as an incentive, exactly as opium acts upon a
Chinaman. The first thing they do the moment they are released is to
forthwith fly off to the nearest other cuckoo-pint. They see a purple,
club-shaped spike, somewhere close by, overtopping the folded lips of
the green hood, and they make straight for that well-known signpost, as
the lordly human race makes for the flaring lights of a gilded public-
house. Once more they crawl down the funnel-shaped tube; once more they
pass the eel-pot hairs; and once more they rub off the pollen that
clings to their legs and sides upon the sensitive surfaces of the lower
flowers. For a while they have again to fast in their narrow prison; and
then the stamens of the second arum open their pollen-sacs, and dust the
greedy insects a second or third time with golden grains. So, throughout
the whole flowering season of the arums, these little flies go about
from head to head in constant relays, unconsciously benefiting the
plant, while they are effecting their own hungry purpose in eating up
the spare pollen. From the point of view of the insects, the only use of
arums is to produce food and shelter for wandering flies; but from the
point of view of the plant, the only use of insects is to act as common
carriers for the conveyance of pollen from one head to another. Man,
however, is far wiser and more expansive in his ideas about the economy
of nature than either: according to him, the real, final end of all this
beautiful and marvellous mechanism is to produce Portland arrowroot for
starching his own civilised shirt-fronts, wristbands, and collars.

After the dissolute small flies have performed their function in the
economy of the cuckoo-pint by thus fertilising the small green ovaries,
the plant begins to enter upon a fresh phase of existence. It has now no
further use for its hood and its purple-topped spike, which have
answered their purpose in attracting the insects; and therefore it gets
rid of them in the same summary way in which mankind generally get rid
of a faithful old horse, or a superannuated servant. The hood withers
slowly away; the top of the spike, as far down as the base of the
cluster of stamens, gradually decays; and at last you find nothing left
but a bunch of rather shapeless green berries, elevated on a stiff,
fleshy stalk, and with a scar at their bottom in the place where the
hood used once to join on. As summer wears away the berries grow bigger
and bigger, while at the same time they become redder and redder. At
last, with the first approach of autumn, they appear as the bright
cluster of coral-coloured berries, represented at the side, with which
we are all so familiar in our September hedgerows.

[Illustration: images/i262.jpg]

Fig. 54.

What is the use of this new manoeuvre? Well, it is not simply that
common to most succulent fruits. Each of these bright red berries
incloses a single hard nut-like seed. Its object is to attract the
fruit-eating birds, the field-mice, and the other small animals, to eat
it up whole. For this end, just as so many flowers have bright-coloured
petals to attract the eyes of insects, we know that fruits have bright-
coloured pulpy coverings to attract the eyes of birds or mammals. And as
the flowers put honey in their nectaries as an allurement for the bees,
so the fruits put sugary juices in their pulp as an allurement for the
robins and bullfinches. So far, the trick is just the ordinary plan of
all fruit-bearers. The arum, however, has a still more cruel and
insidious mode of procedure. Its berries are poisonous; and very often,
I believe, they destroy the little birds that they have enticed by their
delusive prettiness. Then the body of the murdered robin decays away,
and forms a mouldering manure-heap, from which the young cuckoo-pint
derives a store of fresh nutriment. I will not positively assert that it
is for this reason the cuckoo-pint has acquired its poisonous juices;
but I cannot help seeing that if any berry happened to show any tendency
in such a direction, and so occasionally poisoned the creatures which
eat it, it would thereby obtain an advantage in the struggle for
existence, and would tend to increase the poisonous habit so far as it
continued to obtain any further advantage by so doing. To some people
this may seem grotesque; but the grotesqueness is in the facts of
nature, not in the appreciation of their inevitable results. Poisonous
berries are unquestionably useful to the plants which bear them; and, if
we find their usefulness ridiculous, that is a peculiarity of our own
sense of humour which in no way affects the abstract truth of the
observation. It is impossible, in fact, that a plant should not benefit
by having its berries poisonous, and so some plants must necessarily, in
the infinite variability of nature, acquire the property of killing
their friendly allies. It has been asked why the birds have not on their
side learnt that the arum is poisonous. The very question shows at once
an ingrained inability to understand the working of natural selection.
Every bird that eats arum berries gets poisoned: but the other birds
don't hold a coroner's inquest upon its body or inquire into the cause
of death. Naturally the same bird never eats the berries twice, and so
experience has nothing more to do with the matter than in the famous
illogicality about the skinning of eels.

There are many other curious points of interest about the arum: there
are the glossy arrow-headed leaves; there is the sharp, deterrent,
pungent juice; the tall, succulent, biting stem; the thick, starchy,
poisonous root-stock, where the plant lays by the store of nutriment it
collects each summer for next spring's flowering season. All these
demand and repay the minutest and most careful study. But life is too
short for us to know even a cuckoo-pint to the very bottom; and so,
perhaps, instead of turning aside to other subjects of interest in its
structure and functions, it will be best to recapitulate afresh from an
historical point of view the main steps in the evolution of the arum
tribe at which we have already glanced.

Originally, the ancestors of the arum were a sort of lilies, with bright
petals, and with six stamens and a three-celled ovary to each flower.
They had also a papery spathe or hood, like the narcissus and the onion,
at the base of their blossoms; and this spathe has been gradually
modified into the green cap of the modern cuckoo-pint. Slowly the
flowers became reduced in size, like those of acorus; and then they grew
degraded in structure, till at last they entirely lost all their petals
--a stage at which the lower flowers of the Æthiopian lily still remain.
Next, the blossoms began to differentiate into three distinct groups,
which owed their specialised form to the new mode of insect
fertilisation. The lowest flowers lost all their stamens, and were
reduced to a single ovary each. The middle flowers lost all their
ovaries, and were reduced to a few stamens each. The topmost flowers
underwent a still more curious change, and after losing their stamens
made their ovaries abortive, in order to act as eel-traps for the
fertilising flies. The series of alterations by which these structural
modifications were brought about must have been very slow; and they must
have been produced by the constant fertilisation of such arums as best
retained the visiting flies, and the dying out of such as did not well
retain them. Last of all, the berries grew large and red under the
influence of animal selection, those berries which attracted birds
succeeding in producing new plants, while those which did not so attract
them died out unsuccessfully. And at the same time the ovary came to
contain only one seed, instead of three cells with many seeds, because
one seed under the new and improved method of dispersion went as far as
five or ten would have gone under the old and wasteful casual method.
Thus at last what had been a bunch of distinct coloured lilies grew to
be a cuckoo-pint with an inclosing hood and a spike of minute central
inconspicuous flowers.

* * *

## FOOTNOTES:

[1] In all probability, the duckweed is not itself a really primitive
type, but a degraded descendant of higher ancestors. This, however, does
not prevent it from standing as an excellent representative of the real
original unspecialised flowering plant, which must have been quite as
simple in structure.

[2] Of course I do not mean to imply that daisies or primroses are
descended from pinks; that would convey a wholly mistaken notion; but
merely that the ancestors of the daisy once passed through a somewhat
analogous stage.

[3] See fig. 13.

[4] I owe my acknowledgments in much that follows to Mr. A. R. Wallace's
admirable work on _Island Life_.

[5] A lecture delivered at the London Institution, Finsbury Circus.

[6] The sedges are not, in all probability, a real natural family, but
are a group of heterogeneous degraded lilies, containing almost all
those kinds in which the reduced florets are covered by a single
conspicuous glume-like bract. It will be seen from the sequel that these
bracts are not truly homologous to the glumes or outer paleæ of grasses.

[7] See fig. 43.

[8] All the potentillas have a double calyx, which certainly was not the
case with the prime ancestor of the roses, or else the whole tribe would
still retain it.

[9] Botanically and structurally these seeds, as we always call them,
are really fruits; but the point is a purely technical one, with which
it is quite unnecessary to bore the reader. I only mention it here to
anticipate the sharp eyes of botanical critics.

[10] A lecture delivered at the Midland Institute, Birmingham.

[11] It is usual to treat these organs as staminodes--that is to say,
abortive stamens. I know no reason for this classification, and the
analogy of the scattered ovaries in the upper part of the Æthiopian lily
leads me rather to regard them as altered pistils.

* * *

### Transcriber's Notes

Hyphenation has been standardised.

page 52: Bricgstow _changed to_ Brycgstow (Bristol)