Both live on the same soil, as if for mutual aid. The two kingdoms
combine at all points of the globe. We might name a number of places in
which certain plants and certain animals thrive together. The chamois
and the maple tree love the same mountains, the same high places; the
truffle and the earth-worm dwell in the same underground region; the
birch and the hare are found in the same place; the water-lily grows in
the same fresh water with the aquatic worm; and the cod and the algæ
prosper in the same submarine depths.
All vegetables and animals have an original country, but they can
be acclimatized under other skies by human industry and skill. The
chestnut-tree and the Indian cock, the peach-tree and the turkey,
transported to Europe, has each forgotten its native land.
Among both animals and plants there are amphibious creatures. The frog,
and the other batrachians, live, like the reeds, on the earth and in
the water. Both animals and plants can live as parasites. The animal
world has the flea, the louse, the acarus; the vegetable world has its
lichens, and its mushrooms.
Thus, equal fecundity, similar variety in the scale of size, analogy
in habitation, which implies ideality of organization, possibility of
transplantation and of acclimatization out of their original country,
possibility of amphibious existence, parasitical life, all general
conditions which suppose a great analogy of organization; we establish
all these things in drawing the parallel between plants and animals.
How, then, if we grant sensibility to one of these kingdoms, can we
deny it to the other?
6. Plants, like animals, have their maladies. We do not now allude
to maladies caused by parasites, like the sickness of the vine, due
to the _oïdium Tuckeri_, the sickness of the petals, caused by other
small mushrooms, that of the rose-tree, the olive-tree, of corn,
&c., produced by parasitical cryptogams, which fix themselves on the
plant, and change the normal course of its life; we speak of morbid
affections, properly so called. The pathological condition and its
consequences exist in the plant as in the animal. Stoppage, or febrile
and abnormal acceleration of the sap in the vegetable, answer to
stagnation of the blood, or its acceleration during fever, in the
animal; various excrescences of the bark, analogous to affections
of the skin; the abortion of certain organs, and the capricious
development of others; the secretion of pathological liquids which flow
outside. This is a brief catalogue of the maladies to which trees,
shrubs, and herbaceous vegetables are subject. A plant which passes
too quickly and too often from intense cold to extreme heat, soon
becomes ill, and necessarily perishes, like an animal exposed to those
dangerous alterations. A shrub left in a current of cold air could
no more live than an animal if kept in a similar place. In a word,
the plant exhibits health or sickness, according to its conditions of
existence. How can we admit that the being in which such changes take
place, can be merely the passive subject of them, that it experiences
neither pain nor pleasure in passing from health to sickness, or from
sickness to health?
7. Sicknesses, or other causes, produce anomalies of form, or
irregularities of structure in plants, as in animals. Just as in the
animal kingdom _monstrosities_ exist, there are monstrosities in the
vegetable kingdom. The science which occupies itself with monstrosities
in animals is called _teratology_. Geoffrey St. Hilaire has made some
most interesting studies of the causes of the productions of monsters
in the different classes of animals; but it has been perceived of late
that an analogous science must be created, for the explanation of
monstrosities proper to the vegetable kingdom, and Moquin Tandon has
published a book upon _vegetable teratology_.
8. Old age and death are common to both plants and animals. Plants,
after having survived the various maladies which threaten them, do
not escape a slow old age, and death necessarily follows. With time,
their vessels become hardened, their size becomes reduced, they can
no longer give passage to the sap, or other liquids which ought to go
through them. Liquids are not aspired with the same regularity, they no
longer transude through the vegetable tissue with the same precision;
they remain stagnant in the vessels, become corrupt there, and transfer
their decomposition to the vessels which enclose them. Thenceforth
the vital functions cease to be performed, and the plant dies. Things
happen in a like manner among animals. The thickening of the vessels,
the decrease of their power bring on the condition of old age, in
which the functions are disturbed and slackened; then comes death, the
inevitable end of all, in each kingdom of nature.
Thus, when we compare animals and plants, and especially when we
consider the inferior beings in both kingdoms, it is impossible
to establish a precise line of demarcation between them. The
characteristics by which the old naturalists defined the distinction
between plants and animals, are now acknowledged to be without meaning,
and this distinction becomes more and more difficult in proportion as
we make progress in our knowledge of these creatures. Voluntary motion
was regarded as the principal distinctive characteristic between the
two kingdoms of nature; but at the present day this characteristic can
no longer be invoked. Elementary works on botany now tell us about
the fly-catching plant, which catches the insect that crawls over its
leaves, exactly as a spider catches flies, and about the oscillating
plant, whose leaves are endowed by voluntary motion, more distinct than
that belonging to many animals.
Apart from these examples, drawn from classical works, we would ask
what becomes of the argument for the immobility of plants, considered
as a distinctive characteristic of the vegetable kingdom, when we see
that zoophytes are fixed to the earth, and when, on the other hand, we
see certain young plants, or their germs, such as the germs of algæ,
mosses, and ferns, possessing the faculty of motion.
The _spores_, or reproductive organs of algæ, and the _impregnating
corpuscles_ of the mosses and ferns, possess the fundamental
characteristics of animality, that is to say, they are provided
with locomotive organs, and they execute movements which appear to
be voluntary. Those singular creatures are seen to go and come in
the interior of liquids, to endeavour to penetrate into cavities,
to withdraw, return, and definitively introduce themselves with an
apparent effort.
The German botanists regard these vegetable germs as belonging to
the animal kingdom. Considering that only animals have the organs of
motion, and that the spores of algæ and the impregnating corpuscles
of mosses and ferns are provided with organs of motion, they do not
hesitate to declare that in the commencement of their life, algæ,
mosses, and ferns are in truth animals, which become plants when they
fix themselves, and begin to germinate. French botanists have not yet
ventured to adopt that view; they are content to call the movable
impregnating corpuscles of algæ, mosses, and ferns, _antherozoïdes_,
but they do not dare to pronounce upon their animality. M. Pouchet
says, in his work _L'Univers_, page 444:
"Motion manifests itself spontaneously with extraordinary intensity
in the _animalculæ_ of several plants, which have spinal organs for
this purpose, hairs by means of which they swim about in the liquid
which contains them.
"Some of these, real animalcule plants, have the shape of eels, and
move themselves by means of two long filaments attached to their
heads; others exactly resemble the tadpoles of frogs, and jump
about in the cells of the mosses.
"Nevertheless, it is such creatures as these, whose locomotive
organs are so plainly to be discerned, and which we can see,
under the microscope, jumping about as nimbly as our acrobats,
that certain botanists persist in considering, on theory alone,
as motionless and insensible. Some philosophers certainly possess
eyes, that they may not see!"
There are these germs of plants, and young plants which move, and
on the other hand, almost all the adult zoophytes, sponges, corals,
madrepores, sea-stars, byssus, &c., &c., to which we may add several
mollusca (all those in shells), are fixed to the earth. In these cases
we must take the plant for the animal, and the animal for the plant,
if we positively hold by voluntary motion as an absolute distinction
between animals and plants.
On the borders of the two kingdoms,--when we consider zoophytes in the
animal, and cryptogams in the vegetable kingdom,--there is no longer,
so to speak, either animal or plant; the two seem to be confounded, and
fused together.
If, before the discovery of the fresh-water polype, that living
creature had been presented to a naturalist, he would have felt puzzled
how to class it. Seeing it multiplying itself by buds, by offshoots, by
engraftment, he would doubtless have declared that this organized being
was a plant. But if he had been made to remark that this same creature
fed on living prey, which it seized and swallowed, that it had long
and flexible arms, of which it formed a kind of net for the purpose of
seizing this prey, which it conveyed into the interior of a digestive
tube, our naturalist would have made haste to place the polype in the
ranks of the animals. He would have been asked to observe that the
polype may be turned inside out, like a glove, so that his interior
skin becomes his exterior skin, and that, thus turned inside out, he
lives, grows, and multiplies himself, precisely as he does before this
curious reversal. Our naturalist, much embarrassed in the presence of
so unheard of a fact, would doubtless immediately have begun to seek
some intermediate kingdom between the animal and the vegetable, to
which he might relegate this paradoxical being, which could not, with
absolute certainty, be classed either with plants, or with animals.
The fact is, classifications are products of human science, nature
knows nothing about them. We descend, by insensible degrees, from one
kingdom to the other; we go from the man to the polype, and from the
polype to the rose tree, by infinite gradations, and, on the confines
of the two kingdoms, there is a whole series of creatures which it is
very difficult to range under any system. For how long did naturalists
hesitate before they regarded infusoria, coral, sponges, star-fish,
gorgons, sea-anemones, and madrepores as animals? Even in the present
day micrographers who study the microscopic beings proper to vegetable
and animal infusions, such as the monads, polypoid worms, and numerous
others, find the utmost difficulty in assigning these creatures to such
or such a kingdom, and they sometimes decide rather arbitrarily upon
placing them among animals or plants.
From all the considerations, all the facts which we have just advanced,
we conclude that the sensibility of plants is not to be contested,
since no one can think of denying that privilege to certain zoophytes
which can with difficulty be distinguished from vegetables.
We see an imposing tree, a stately oak with sturdy branches, growing on
the sea coast. Not far off, on the sand of the shore, lies a star-fish
flung there by the waves. A few yards below, on the surface of the
water, floats a sponge, a branch of coral, a madrepore. When the icy
wind blows, when the hurricane lifts the angry waves, which is it, the
animal or the plant that will manifest sensibility to the tempest? The
sponge, the coral, the madrepore will remain as indifferent to the fury
of the elements as the rock in which they are incrusted, or as the
pebble on which the star-fish stretches out its four motionless arms.
But, the majestic oak will shudder at every gust of the tempest; he
will bend his branches and shut up his leaves to shelter himself from
the icy blast or the furious storm; and a mere glance at his attitude
will indicate to you that an abnormal perturbation reigns in the
atmosphere. Would you seriously say, in that case, that the vegetable
feels nothing, and that the animal is sensible? Would you not, on the
contrary, be inclined to declare that the tree is the sentient being,
and that the star-fish, the sponge, the madrepore, are the creatures
which are destitute of feeling?
Pause beside still water and seek for the polype or fresh-water hydra
which we have just mentioned. You will find it difficult to disentangle
this zoophyte from the reeds and willows which surround it. You will
find, at length, a kind of membranous tube, a few centimetres in
length. Is that the polype you were looking for? Is it not rather the
stubble of some reed or grass plant? This living twig, with nothing to
distinguish it in appearance from a herbaceous plant, is constantly
fixed in the same place, like an aquatic vegetable. It makes some
faint movements, consisting simply of the opening and shutting of the
orifice of the tube, which solely constitutes its being. Sometimes it
lengthens, sometimes it contracts itself, by stretching out membranous
arms, as fine as threads, by means of which it seizes and drags towards
it the water insects which chance to pass near it. This is the one
single characteristic of its animality. At this rate, an aërial plant,
the _fly-catcher_, would be just as much an animal as our polype, since
it catches the insects which venture to crawl upon its leaves.
At the bottom of the sea there is a very curious zoophyte, the
_actinium_, or sea-anemone. For a long time this creature was
confounded with the plants, and held to be an ocean flower. Those
who admire the beautiful, bright-coloured actinia, in the Garden
of Acclimatization, in Paris, who look at them, waving on their
flexible stem, shaking the coloured appendages and fringes which adorn
their heads, find it hard to regard these charming queens of the
waters otherwise than as real flowers. And, in fact, for ages, the
_sea-anemones_ were held to be marine plants.
In the last century, coral was held to be a marine shrub, and it was
even believed that the flowers of the coral had been discovered. An
academician of Paris, Count de Marsigli, created a European reputation
for himself by this supposed discovery. Peyssonnel, a Provençal
naturalist, found the utmost difficulty in opposing this idea, and in
establishing the fact that these supposed flowers of the coral were
in reality young corals. He had the whole Academy of Sciences against
him; and his opposition to the ideas of the Academy brought him into
such disgrace, that he was obliged to leave France and to go to the
Antilles, where he died in obscurity as a doctor of medicine. And all
this because he maintained that coral is not a plant, and does not
produce flowers!
The famous Genevese naturalist, Charles Bonnet, anticipating the
knowledge of our day by more than a century, has given a most
interesting form to the parallel between animals and plants, in his
work entitled _Contemplation de la Nature_. We cannot resist the
pleasure of quoting the following passage, in which Charles Bonnet
shows in a striking manner what are the difficulties in the way of
distinguishing the plant from the animal, and how those difficulties
are disposed of by those who dispute the sensibility of plants:--
"Everything is graduated in nature," says Charles Bonnet, "and, in
refusing to admit that plants are sentient, we force nature to make
a jump without any assignable reason.
"We observe that feeling decreases by degrees from man to the
nettle, and to the mussel, and we persuade ourselves that it stops
there, because we regard these animals as the least perfect. But
there are, perhaps, many degrees between the feeling of the mole
and of the plant. There are, perhaps, still more between the most
and the least sensible of the plants. The gradations, which we
observe, ought to persuade us to this philosophy; the new beauty
which it adds to the system of the world, and the pleasure to be
derived from the multiplication of sentient creatures ought to
contribute to induce us to admit it. I willingly admit that this
philosophy is much to my taste. I love to think that those flowers
which adorn our fields and our gardens with a brightness constantly
renewed, those fruit trees which are so pleasant to our eyes and
our palate; those majestic trees that compose the vast forests,
which time seems to have respected, are so many sentient creatures
partaking after their fashion in the sweetness of existence.
"Plants offer some facts to our observation which seem to indicate
that they possess feeling, but we are not likely to perceive those
facts, because of the strong persuasion that they are insensible,
which has prevailed among us for so long. We ought to agree to
consider the question _tabula rasa_, and to subject plants to
a new, impartial, and unprejudiced examination. An inhabitant
of the moon, possessed of intellectual faculties like ours, but
without any preconceived ideas about the insensibility of plants,
would be the philosopher whom we require. Let us imagine such
an observer engaged in studying the productions of our earth,
and, after having given his attention to the polypes and other
insects multiplied by the process of grafting, passing on to the
contemplation of vegetables. He would, doubtless, take them at
the period of their birth. With this view, he would sow seed of
various species, and he would carefully watch their germination.
Let us suppose that some of those seeds have been reversed in the
sowing, the sprouting part turned downwards, the stem upwards; and
the observer has the skill to distinguish one end of the seed from
the other, and knows their functions. After some days, he will
remark that the seed has grown into this reversed position, that
the stem is turned upward, and the sprouting portion downward. He
will feel no surprise; he will attribute a circumstance which is
so hurtful to the life of the plant, to the mistake he has made in
sowing the seed. But, continuing to observe, he will see the sprout
and the stem each bending itself in the opposite direction, and
trying to attain the right position. This change of direction will
strike him as very remarkable, and he will begin to suspect that
the organized being which he is studying is endowed with a certain
amount of discernment. Too prudent, however, to pronounce upon
these early indications, he will suspend his judgment and pursue
his investigations. The plants whose germination our physicist
has been observing, have been raised in the neighbourhood of a
hedge. Thus favoured, and carefully cultivated, they have made
great progress in a very short time. The soil which surrounds them
at some distance is of two opposite qualities. That on the right
of the plants is rich, damp, and spongy; that on the left is dry,
hard, and gravelly. Our observer remarks that the roots, after
having begun by extending equally on both sides, have changed their
direction, and have spread out towards the rich and humid soil;
over which they are stretching, and thus threatening to deprive
the plants already there of their due share of nourishment. To
prevent this inconvenience, he digs a ditch between the plants
which he is observing and those they threaten to starve, and now he
thinks he has provided against everything. But the plants, which
he believes he has governed, disconcert all his precautions by
extending their roots downwards, under the ditch, and gaining the
other side.
"Surprised at this, he uncovers one of these roots, but without
exposing it to heat, and holds a sponge steeped in water towards
it. The root turns itself to the sponge, and when he changes its
position, the root accommodates itself to each alteration.
"While our philosopher is meditating profoundly upon these
facts, other facts equally remarkable present themselves almost
simultaneously. He observes that all these plants have leaned away
from the hedge, and are bending forward as though to present every
portion of their bodies to the beneficent smiles of the sun. He
sees that all the leaves are so turned that their upper surface is
exposed to the sun, or to the fresh air, and that the lower surface
is directed towards the hedge, or the ground. Former experience
will have taught him that the upper surface of leaves serves
chiefly as a defence for the lower surface, and that the latter
is principally destined to pump up the moisture rising from the
earth, and provide for the evacuation of what is superfluous. The
direction of the leaves which he notices appears quite in harmony
with his experiences. He studies this portion of the plant with
increased attention.
"He remarks that the leaves of some species seem to follow the
movements of the sun, so that in the morning they turn to the
east, in the evening to the west. He sees that some leaves close
themselves against the sun, others against the dew. He observes an
analogous movement in certain flowers. Afterwards, he observes
that no matter what the direction of the plants relative to the
horizon has been, the direction of the leaves is always that
which he has at first noticed, he bethinks him of changing this
direction, and of placing the leaves in a position exactly contrary
to their natural one. He has already had recourse to similar
means in order to assure himself of the instinct of animals, and
to ascertain its bearings. With this view he bends perpendicular
plants towards the horizon, and keeps them in that position. Thus,
the direction of the leaves is absolutely changed; the upper
surface, which previously turned to the sun or to the fresh air,
now looks towards the earth or the interior of the plant, and the
lower surface, which formerly looked towards the earth or the
interior of the plant, now turns to the sun, or the fresh air. But
very soon all these leaves begin to move, they turn on their stem
as on a pivot, and in an hour they will have resumed their former
position. Our observer, wishing to assure himself whether leaves
and branches when detached and plunged into water will preserve
the inclinations which they manifest when upon the plant of which
they formed a portion, subjects them to an experiment whose results
leave him no doubt of the fact.
"He places wet sponges under the leaves, and he sees the leaves
turn towards the sponges and endeavour to adhere to them by their
lower surfaces. He also observes that certain plants, which he has
shut up in his cabinet and in a cellar, have turned towards the
window, or the grating respectively.
"Finally, the phenomena of the Sensitive Plant, its varied
movements, the promptitude with which it contracts when touched,
form the interesting subject which terminates his researches.
"Thus plentifully supplied with facts which all seem to tend to the
support of belief in the sensibility of plants, which side will
our philosopher take? Will he surrender to these proofs? Will he
suspend his judgment? I think he will take the first part."[16]
Charles Bonnet believes, in short, that the plant, as well as the
animal, is endowed with sensibility.
According to the system which we have developed, the animal is
possessed of a soul, which is still very imperfect, and endowed only
with faculties corresponding to its needs. But, since the animal,
in addition to the sensibility enjoyed by the plant, possesses
intelligence also, we must conclude from thence that the plant has not
a soul, properly so called, but only the rudiment, the commencement, in
other words, the _germ_ of a soul.
We know that the sun has the privilege of giving birth to organic life
upon our globe, his rays have power to produce the formation of living
tissues, plants or zoophytes, when they fall upon the earth or the
waters, and we may draw this conclusion from all that has gone before,
that the sun sends down upon the earth _animated germs_ under the form
of his rays, which emanate from the spiritualized creatures who dwell
in the king-star.