II

"I can entertain no doubt, after the most deliberate study and

dispassionate judgment of which I am capable, that the view which most

naturalists entertain, and which I formerly entertained, namely, that

each species has been independently created, is erroneous. I am fully

convinced that species are not immutable; but that those belonging to

what are called the same genera are lineal descendants of some other

and generally extinct species, in the same manner as the acknowledged

varieties of any one species are the descendants of that species.

Furthermore, I am convinced that Natural Selection has been the main,

but not exclusive, means of modification."

This is the kernel of the new theory, the Darwinian creed, as recited

at the close of the introduction to the remarkable book under

consideration. The questions, "What will he do with it?" and "How far

will he carry it?" the author answers at the close of the volume:

"I cannot doubt that the theory of descent with modification embraces

all the members of the same class." Furthermore, "I believe that all

animals have descended from at most only four or five progenitors, and

plants from an equal or lesser number."

Seeing that analogy as strongly suggests a further step in the same

direction, while he protests that "analogy may be a deceitful guide,"

yet he follows its inexorable leading to the inference that--

"Probably all the organic beings which have ever lived on this ear have

descended from some one primordial form, into which life was first

breathed."[III-4]

In the first extract we have the thin end of the wedge driven a little

way; in the last, the wedge driven home.

We have already sketched some of the reasons suggestive of such a

theory of derivation of species, reasons which gave it plausibility,

and even no small probability, as applied to our actual world and to

changes occurring since the latest tertiary period. We are well pleased

at this moment to find that the conclusions we were arriving at in this

respect are sustained by the very high authority and impartial judgment

of Pictet, the Swiss paleontologist. In his review of Darwins

book[III-5] -- the fairest and most admirable opposing one that has

appeared--he freely accepts that ensemble of natural operations which

Darwin impersonates under the now familiar name of Natural Selection,

allows that the exposition throughout the first chapters seems "a la

fois prudent et fort," and is disposed to accept the whole argument in

its foundations, that is, so far as it relates to what is now going on,

or has taken place in the present geological period--which period he

carries back through the diluvial epoch to the borders of the

tertiary.[III-6] Pictet accordingly admits that the theory will very

well account for the origination by divergence of nearly-related

species, whether within the present period or in remoter geological

times; a very natural view for him to take, since he appears to have

reached and published, several years ago, the pregnant conclusion that

there most probably was some material connection between the

closely-related species of two successive faunas, and that the numerous

close species, whose limits are so difficult to determine, were not all

created distinct and independent. But while thus accepting, or ready

to accept, the basis of Darwins theory, and all its legitimate direct

inferences, he rejects the ultimate conclusions, brings some weighty

arguments to bear against them, and is evidently convinced that he can

draw a clear line between the sound inferences, which he favors, and

the unsound or unwarranted theoretical deductions, which he rejects. We

hope he can.

This raises the question, Why does Darwin press his theory to these

extreme conclusions? Why do all hypotheses of derivation converge so

inevitably to one ultimate point? Having already considered some of the

reasons which suggest or support the theory at its outset--which may

carry it as far as such sound and experienced naturalists as Pictet

allow that it may be true--perhaps as far as Darwin himself unfolds it

in the introductory proposition cited at the beginning of this

article--we may now inquire after the motives which impel the theorist

so much farther. Here proofs, in the proper sense of the word, are not

to be had. We are beyond the region of demonstration, and have only

probabilities to consider. What are these probabilities? What work will

this hypothesis do to establish a claim to be adopted in its

completeness? Why should a theory which may plausibly enough account

for the diversification of the species of each special type or genus be

expanded into a general system for the origination or successive

diversification of all species, and all special types or forms, from

four or five remote primordial forms, or perhaps from one? We accept

the theory of gravitation because it explains all the facts we know,

and bears all the tests that we can put it to. We incline to accept the

nebular hypothesis, for similar reasons; not because it is proved--thus

far it is incapable of proof--but because it is a natural theoretical

deduction from accepted physical laws, is thoroughly congruous with the

facts, and because its assumption serves to connect and harmonize these

into one probable and consistent whole. Can the derivative hypothesis

be maintained and carried out into a system on similar grounds? If so,

however unproved, it would appear to be a tenable hypothesis, which is

all that its author ought now to claim. Such hypotheses as, from the

conditions of the case, can neither be proved nor disproved by direct

evidence or experiment, are to be tested only indirectly, and therefore

imperfectly, by trying their power to harmonize the known facts, and to

account for what is otherwise unaccountable. So the question comes to

this: What will an hypothesis of the derivation of species explain

which the opposing view leaves unexplained?

Questions these which ought to be entertained before we take up the

arguments which have been advanced against this theory. We can barely

glance at some of the considerations which Darwin adduces, or will be

sure to adduce in the future and fuller exposition which is promised.

To display them in such wise as to indoctrinate the unscientific reader

would require a volume. Merely to refer to them in the most general

terms would suffice for those familiar with scientific matters, but

would scarcely enlighten those who are not. Wherefore let these trust

the impartial Pictet, who freely admits that, "in the absence of

sufficient direct proofs to justify the possibility of his hypothesis,

Mr. Darwin relies upon indirect proofs, the bearing of which is real

and incontestable;" who concedes that "his theory accords very well

with the great facts of comparative anatomy and zoology--comes in

admirably to explain unity of composition of organisms, also to explain

rudimentary and representative organs, and the natural series of genera

and species--equally corresponds with many paleontological data--agrees

well with the specific resemblances which exist between two successive

faunas, with the parallelism which is sometimes observed between the

series of paleontological succession and of embryonal development,"

etc.; and finally, although he does not accept the theory in these

results, he allows that "it appears to offer the best means of

explaining the manner in which organized beings were produced in epochs

anterior to our own."

What more than this could be said for such an hypothesis? Here,

probably, is its charm, and its strong hold upon the speculative mind.

Unproven though it be, and cumbered prima facie with cumulative

improbabilities as it proceeds, yet it singularly accords with great

classes of facts otherwise insulated and enigmatic, and explains many

things which are thus far utterly inexplicable upon any other

scientific assumption.

We have said that Darwins hypothesis is the natural complement to

Lyells uniformitarian theory in physical geology. It is for the organic

world what that is for the inorganic; and the accepters of the latter

stand in a position from which to regard the former in the most

favorable light. Wherefore the rumor that the cautious Lyell himself

has adopted the Darwinian hypothesis need not surprise us. The two

views are made for each other, and, like the two counterpart pictures

for the stereoscope, when brought together, combine into one apparently

solid whole.

If we allow, with Pictet, that Darwins theory will very well serve for

all that concerns the present epoch of the worlds history--an epoch in

which this renowned paleontologist includes the diluvial or quaternary

period--then Darwins first and foremost need in his onward course is a

practicable road from this into and through the tertiary period, the

intervening region between the comparatively near and the far remote

past. Here Lyells doctrine paves the way, by showing that in the

physical geology there is no general or absolute break between the two,

probably no greater between the latest tertiary and the quaternary

period than between the latter and the present time. So far, the

Lyellian view is, we suppose, generally concurred in. It is largely

admitted that numerous tertiary species have continued down into the

quaternary, and many of them to the present time. A goodly percentage

of the earlier and nearly half of the later tertiary mollusca,

according to Des Hayes, Lye!!, and, if we mistake not, Bronn, still

live. This identification, however, is now questioned by a naturalist

of the very highest authority. But, in its bearings on the new theory,

the point here turns not upon absolute identity so much as upon close

resemblance. For those who, with Agassiz, doubt the specific identity

in any of these cases, and those who say, with Pictet, that "the later

tertiary deposits contain in general the debris of species very nearly

related to those which still exist, belonging to the same genera, but

specifically different," may also agree with Pictet, that the

nearly-related species of successive faunas must or may have had "a

material connection." But the only material connection that we have an

idea of in such a case is a genealogical one. And the supposition of a

genealogical connection is surely not unnatural in such cases--is

demonstrably the natural one as respects all those tertiary species

which experienced naturalists have pronounced to be identical with

existing ones, but which others now deem distinct For to identify the

two is the same thing as to conclude the one to be the ancestor of the

other No doubt there are differences between the tertiary and the

present individuals, differences equally noticed by both classes of

naturalists, but differently estimated By the one these are deemed

quite compatible, by the other incompatible, with community of origin

But who can tell us what amount of difference is compatible with

community of origin? This is the very question at issue, and one to be

settled by observation alone Who would have thought that the peach and

the nectarine came from one stock? But, this being proved is it now

very improbable that both were derived from the almond, or from some

common amygdaline progenitor? Who would have thought that the cabbage,

cauliflower, broccoli kale, and kohlrabi are derivatives of one

species, and rape or colza, turnip, and probably ruta-baga, of another

species? And who that is convinced of this can long undoubtingly hold

the original distinctness of turnips from cabbages as an article of

faith? On scientific grounds may not a primordial cabbage or rape be

assumed as the ancestor of all the cabbage races, on much the same

ground that we assume a common ancestry for the diversified human

races? If all Our breeds of cattle came from one stock why not this

stock from the auroch, which has had all the time between the diluvial

and the historic periods in which to set off a variation perhaps no

greater than the difference between some sorts of domestic cattle?

That considerable differences are often discernible between tertiary

individuals and their supposed descendants of the present day affords

no argument against Darwins theory, as has been rashly thought, but is

decidedly in its favor. If the identification were so perfect that no

more differences were observable between the tertiary and the recent

shells than between various individuals of either, then Darwins

opponents, who argue the immutability of species from the ibises and

cats preserved by the ancient Egyptians being just like those of the

present day, could triumphantly add a few hundred thousand years more

to the length of the experiment and to the force of their argument.

As the facts stand, it appears that, while some tertiary forms are

essentially undistinguishable from existing ones, others are the same

with a difference, which is judged not to be specific or aboriginal;

and yet others show somewhat greater differences, such as are

scientifically expressed by calling them marked varieties, or else

doubtful species; while others, differing a little more, are

confidently termed distinct, but nearly-related species. Now, is not

all this a question of degree, of mere gradation of difference? And is

it at all likely that these several gradations came to be established

in two totally different ways--some of them (though naturalists cant

agree which) through natural variation, or other secondary cause, and

some by original creation, without secondary cause? We have seen that

the judicious Pictet answers such questions as Darwin would have him

do, in affirming that, in all probability, the nearly-related species

of two successive faunas were materially connected, and that

contemporaneous species, similarly resembling each other, were not all

created so, but have become so. This is equivalent to saying that

species (using the term as all naturalists do, and must continue to

employ the word) have only a relative, not an absolute fixity; that

differences fully equivalent to what are held to be specific may arise

in the course of time, so that one species may at length be naturally

replaced by another species a good deal like it, or may be diversified

into two, three, or more species, or forms as different as species.

This concedes all that Darwin has a right to ask, all that he can

directly infer from evidence. We must add that it affords a locus

standi, more or less tenable, for inferring more.

Here another geological consideration comes in to help on this

inference. The species of the later tertiary period for the most part

not only resembled those of our days--many of them so closely as to

suggest an absolute continuity--but also occupied in general the same

regions that their relatives occupy now. The same may be said, though

less specially, of the earlier tertiary and of the later secondary; but

there is less and less localization of forms as we recede, yet some

localization even in palaeozoic times. While in the secondary period

one is struck with the similarity of forms and the identity of many of

the species which flourished apparently at the same time in all or in

the most widely-separated parts of the world, in the tertiary epoch, on

the contrary, along with the increasing specialization of climates and

their approximation to the present state, we find abundant evidence of

increasing localization of orders, genera and species, and this

localization strikingly accords with the present geographical

distribution of the same groups of species Where the imputed

forefathers lived their relatives and supposed descendants now flourish

All the actual classes of the animal and vegetable kingdoms were

represented in the tertiary faunas and floras and in nearly the same

proportions and the same diversities as at present The faunas of what

is now Europe, Asia America and Australia, differed from each other

much as they now differ: in fact--according to Adolphe Brongniart,

whose statements we here condense[III-7]--the inhabitants of these

different regions appear for the most part to have acquired, before the

close of the tertiary period, the characters which essentially

distinguish their existing faunas. The Eastern Continent had then, as

now, its great pachyderms, elephants, rhinoceros, hippopotamus; South

America, its armadillos, sloths, and anteaters; Australia, a crowd of

marsupials; and the very strange birds of New Zealand had predecessors

of similar strangeness.

Everywhere the same geographical distribution as now, with a difference

in the particular area, as respects the northern portion of the

continents, answering to a warmer climate then than ours, such as

allowed species of hippopotamus, rhinoceros, and elephant, to range

even to the regions now inhabited by the reindeer and the musk-ox, and

with the serious disturbing intervention of the glacial period within a

comparatively recent time. Let it be noted also that those tertiary

species which have continued with little change down to our days are

the marine animals of the lower grades, especially mollusca. Their low

organization, moderate sensibility, and the simple conditions of an

existence in a medium like the ocean, not subject to great variation

and incapable of sudden change, may well account for their continuance;

while, on the other hand, the more intense, however gradual, climatic

vicissitudes on land, which have driven all tropical and subtropical

forms out of the higher latitudes and assigned to them their actual

limits, would be almost sure to extinguish such huge and unwieldy

animals as mastodons, mammoths, and the like, whose power of enduring

altered circumstances must have been small.

This general replacement of the tertiary species of a country by others

so much like them is a noteworthy fact. The hypothesis of the

independent creation of all species, irrespective of their antecedents,

leaves this fact just as mysterious as is creation itself; that of

derivation undertakes to account for it. Whether it satisfactorily does

so or not, it must be allowed that the facts well accord with that

hypothesis. The same may be said of another conclusion, namely, that

the geological succession of animals and plants appears to correspond

in a general way with their relative standing or rank in a natural

system of classification. It seems clear that, though no one of the

grand types of the animal kingdom can be traced back farther than the

rest, yet the lower classes long preceded the higher; that there has

been on the whole a steady progression within each class and order; and

that the highest plants and animals have appeared only in relatively

modern times. It is only, however, in a broad sense that this

generalization is now thought to hold good. It encounters many apparent

exceptions, and sundry real ones. So far as the rule holds, all is as

it should be upon an hypothesis of derivation.

The rule has its exceptions. But, curiously enough, the most striking

class of exceptions, if such they be, seems to us even more favorable

to the doctrine of derivation than is the general rule of a pure and

simple ascending gradation. We refer to what Agassiz calls prophetic

and synthetic types; for which the former name may suffice, as the

difference between the two is evanescent.

"It has been noticed," writes our great zoologist, "that certain types,

which are frequently prominent among the representatives of past ages,

combine in their structure peculiarities which at later periods are

only observed separately in different, distinct types. Sauroid fishes

before reptiles, Pterodactyles before birds, Ichthyosauri before

dolphins, etc. There are entire families, of nearly every class of

animals, which in the state of their perfect development exemplify such

prophetic relations.

The sauroid fishes of the past geological ages are an example of this

kind These fishes which preceded the appearance of reptiles present a

combination of ichthyic and reptilian characters not to be found in the

true members of this class, which form its bulk at present. The

Pterodactyles, which preceded the class of birds, and the Ichthyosauri,

which preceded the Cetacea, are other examples of such prophetic

types."--(Agassiz, "Contributions, Essay on Classification," p. 117.)

Now, these reptile-like fishes, of which gar-pikes are the living

representatives, though of earlier appearance, are admittedly of higher

rank than common fishes. They dominated until reptiles appeared, when

they mostly gave place to (or, as the derivationists will insist, were

resolved by divergent variation and natural selection into) common

fishes, destitute of reptilian characters, and saurian reptiles--the

intermediate grades, which, according to a familiar piscine saying, are

"neither fish, flesh, nor good red-herring," being eliminated and

extinguished by natural consequence of the struggle for existence which

Darwin so aptly portrays. And so, perhaps, of the other prophetic

types. Here type and antitype correspond. If these are true prophecies,

we need not wonder that some who read them in Agassizs book will read

their fulfillment in Darwins.

Note also, in this connection, that along with a wonderful persistence

of type, with change of species, genera, orders, etc., from formation

to formation, no species and no higher group which has once

unequivocally died out ever afterward reappears. Why is this, but that

the link of generation has been sundered? Why, on the hypothesis of

independent originations, were not failing species recreated, either

identically or with a difference, in regions eminently adapted to their

well-being? To take a striking case. That no part of the world now

offers more suitable conditions for wild horses and cattle than the

pampas and other plains of South America, is shown by the facility with

which they have there run wild and enormously multiplied, since

introduced from the Old World not long ago. There was no wild American

stock. Yet in the times of the mastodon and megatherium, at the dawn of

the present period, wild-horses--certainly very much like the existing

horse--roamed over those plains in abundance. On the principle of

original and direct created adaptation of species to climate and other

conditions, why were they not reproduced, when, after the colder

intervening era, those regions became again eminently adapted to such

animals? Why, but because, by their complete extinction in South

America, the line of descent was there utterly broken? Upon the

ordinary hypothesis, there is no scientific explanation possible of

this series of facts, and of many others like them. Upon the new

hypothesis, "the succession of the same types of structure within the

same areas during the later geological periods ceases to be mysterious,

and is simply explained by inheritance." Their cessation is failure of

issue.

Along with these considerations the fact (alluded to on page 98) should

be remembered that, as a general thing, related species of the present

age are geographically associated. The larger part of the plants, and

still more of the animals, of each separate country are peculiar to it;

and, as most species now flourish over the graves of their by-gone

relatives of former ages, so they now dwell among or accessibly near

their kindred species.

Here also comes in that general "parallelism between the order of

succession of animals and plants in geological times, and the gradation

among their living representatives" from low to highly organized, from

simple and general to complex and specialized forms; also "the

parallelism between the order of succession of animals in geological

times and the changes their living representatives undergo during their

embryological growth," as if the world were one prolonged gestation.

Modern science has much insisted on this parallelism, and to a certain

extent is allowed to have made it out. All these things, which conspire

to prove that the ancient and the recent forms of life "are somehow

intimately connected together in one grand system," equally conspire to

suggest that the connection is one similar or analogous to generation.

Surely no naturalist can be blamed for entering somewhat confidently

upon a field of speculative inquiry which here opens so invitingly; nor

need former premature endeavors and failures utterly dishearten him.

All these things, it may naturally be said, go to explain the order,

not the mode, of the incoming of species. But they all do tend to bring

out the generalization expressed by Mr. Wallace in the formula that

"every species has come into existence coincident both in time and

space with preexisting closely-allied species." Not, however, that this

is proved even of existing species as a matter of general fact. It is

obviously impossible to prove anything of the kind. But we must concede

that the known facts strongly suggest such an inference. And--since

species are only congeries of individuals, since every individual came

into existence in consequence of preexisting individuals of the same

sort, so leading up to the individuals with which the species began,

and since the only material sequence we know of among plants and

animals is that from parent to progeny--the presumption becomes

exceedingly strong that the connection of the incoming with the

preexisting species is a genealogical one.

Here, however, all depends upon the probability that Mr. Wallaces

inference is really true. Certainly it is not yet generally accepted;

but a strong current is setting toward its acceptance.

So long as universal cataclysms were in vogue, and all life upon the

earth was thought to have been suddenly destroyed and renewed many

times in succession, such a view could not be thought of. So the

equivalent view maintained by Agassiz, and formerly, we believe, by

DOrbigny, that irrespectively of general and sudden catastrophes, or

any known adequate physical cause, there has been a total depopulation

at the close of each geological period or formation, say forty or fifty

times or more, followed by as many independent great acts of creation,

at which alone have species been originated, and at each of which a

vegetable and an animal kingdom were produced entire and complete,

full-fledged, as flourishing, as wide-spread, and populous, as varied

and mutually adapted from the beginning as ever afterward--such a view,

of course, supersedes all material connection between successive

species, and removes even the association and geographical range of

species entirely out of the domain of physical causes and of natural

science. This is the extreme opposite of Wallaces and Darwin s view,

and is quite as hypothetical. The nearly universal opinion, if we

rightly gather it, manifestly is, that the replacement of the species

of successive formations was not complete and simultaneous, but partial

and successive; and that along the course of each epoch some species

probably were introduced, and some, doubtless, became extinct. If all

since the tertiary belongs to our present epoch, this is certainly true

of it: if to two or more epochs, then the hypothesis of a total change

is not true of them.

Geology makes huge demands upon time; and we regret to find that it has

exhausted ours--that what we meant for the briefest and most general

sketch of some geological considerations in favor of Darwins hypothesis

has so extended as to leave no room for considering "the great facts of

comparative anatomy and zoology" with which Darwins theory "very well

accords," nor for indicating how "it admirably serves for explaining

the unity of composition of all organisms, the existence of

representative and rudimentary organs, and the natural series which

genera and species compose." Suffice it to say that these are the real

strongholds of the new system on its theoretical side; that it goes far

toward explaining both the physiological and the structural gradations

and relations between the two kingdoms, and the arrangement of all

their forms in groups subordinate to groups, all within a few great

types; that it reads the riddle of abortive organs and of morphological

conformity, of which no other theory has ever offered a scientific

explanation, and supplies a ground for harmonizing the two fundamental

ideas which naturalists and philosophers conceive to have ruled the

organic world, though they could not reconcile them; namely, Adaptation

to Purpose and Conditions of Existence, and Unity of Type. To reconcile

these two undeniable principles is the capital problem in the

philosophy of natural history; and the hypothesis which consistently

does so thereby secures a great advantage.

We all know that the arm and hand of a monkey, the foreleg and foot of

a dog and of a horse, the wing of a bat, and the fin of a porpoise, are

fundamentally identical; that the long neck of the giraffe has the same

and no more bones than the short one of the elephant; that the eggs of

Surinam frogs hatch into tadpoles with as good tails for swimming as

any of their kindred, although as tadpoles they never enter the water;

that the Guinea-pig is furnished with incisor teeth which it never

uses, as it sheds them before birth; that embryos of mammals and birds

have branchial slits and arteries running in loops, in imitation or

reminiscence of the arrangement which is permanent in fishes; and that

thousands of animals and plants have rudimentary organs which, at least

in numerous cases, are wholly useless to their possessors, etc., etc.

Upon a derivative theory this morphological conformity is explained by

community of descent; and it has not been explained in any other way.

Naturalists are constantly speaking of "related species," of the

"affinity" of a genus or other group, and of "family

resemblance"--vaguely conscious that these terms of kinship are

something more than mere metaphors, but unaware of the grounds of their

aptness. Mr. Darwin assures them that they have been talking derivative

doctrine all their lives--as M. Jourdain talked prose--without knowing

it.

If it is difficult and in many cases practically impossible to fix the

limits of species, it is still more so to fix those of genera; and

those of tribes and families are still less susceptible of exact

natural circumscription. Intermediate forms occur, connecting one group

with another in a manner sadly perplexing to systematists, except to

those who have ceased to expect absolute limitations in Nature. All

this blending could hardly fail to suggest a former material connection

among allied forms, such as that which the hypothesis of derivation

demands.

Here it would not be amiss to consider the general principle of

gradation throughout organic Nature--a principle which answers in a

general way to the Law of Continuity in the inorganic world, or rather

is so analogous to it that both may fairly be expressed by the

Leibnitzian axiom, Natura non agit saltatim. As an axiom or

philosophical principle, used to test modal laws or hypotheses, this in

strictness belongs only to physics. In the investigation of Nature at

large, at least in the organic world, nobody would undertake to apply

this principle as a test of the validity of any theory or supposed law.

But naturalists of enlarged views will not fail to infer the principle

from the phenomena they investigate--to perceive that the rule holds,

under due qualifications and altered forms, throughout the realm of

Nature; although we do not suppose that Nature in the organic world

makes no distinct steps, but only short and serial steps--not

infinitely fine gradations, but no long leaps, or few of them.

To glance at a few illustrations out of many that present themselves.

It would be thought that the distinction between the two organic

kingdoms was broad and absolute. Plants and animals belong to two very

different categories, fulfill opposite offices and, as to the mass of

them are so unlike that the difficulty of the ordinary observer would

be to find points of comparison Without entering into details which

would fill an article, we may safely say that the difficulty with the

naturalist is all the other way--that all these broad differences

vanish one by one as we approach the lower confines of the two

kingdoms, and that no absolute distinction whatever is now known

between them. It is quite possible that the same organism may be both

vegetable and animal, or may be first the one and then the other. If

some organisms may be said to be at first vegetables and then animals,

others, like the spores and other reproductive bodies of many of the

lower Algae, may equally claim to have first a characteristically

animal, and then an unequivocally vegetable existence. Nor is the

gradation restricted to these simple organisms. It appears in general

functions, as in that of reproduction, which is reducible to the same

formula in both kingdoms, while it exhibits close approximations in the

lower forms; also in a common or similar ground of sensibility in the

lowest forms of both, a common faculty of effecting movements tending

to a determinate end, traces of which pervade the vegetable

kingdom--while, on the other hand, this indefinable principle, this

vegetable

"Animula vagula, blandula, Hospes comesque corporis,"

graduates into the higher sensitiveness of the lower class of animals.

Nor need we hesitate to recognize the fine gradations from simple

sensitiveness and volition to the higher instinctive and to the other

psychical manifestations of the higher brute animals. The gradation is

undoubted, however we may explain it.

Again, propagation is of one mode in the higher animals, of two in all

plants; but vegetative propagation, by budding or offshoots, extends

through the lower grades of animals. In both kingdoms there may be

separation of the offshoots, or indifference in this respect, or

continued and organic union with the parent stock; and this either with

essential independence of the offshoots, or with a subordination of

these to a common whole; or finally with such subordination and

amalgamation, along with specialization of function, that the same

parts, which in other cases can be regarded only as progeny, in these

become only members of an individual.

This leads to the question of individuality, a subject quite too large

and too recondite for present discussion. The conclusion of the whole

matter, however, is, that individuality--that very ground of being as

distinguished from thing--is not attained in Nature at one leap. If

anywhere truly exemplified in plants, it is only in the lowest and

simplest, where the being is a structural unit, a single cell,

member-less and organless, though organic--the same thing as those

cells of which all the more complex plants are built up, and with which

every plant and (structurally) every animal began its development. In

the ascending gradation of the vegetable kingdom individuality is, so

to say, striven after, but never attained; in the lower animals it is

striven after with greater though incomplete success; it is realized

only in animals of so high a rank that vegetative multiplication or

offshoots are out of the question, where all parts are strictly members

and nothing else, and all subordinated to a common nervous centre--is

fully realized only in a conscious person.

So, also, the broad distinction between reproduction by seeds or ova

and propagation by buds, though perfect in some of the lowest forms of

life, becomes evanescent in others; and even the most absolute law we

know in the physiology of genuine reproduction--that of sexual

cooperation--has its exceptions in both kingdoms in parthenogenesis, to

which in the vegetable kingdom a most curious and intimate series of

gradations leads. In plants, likewise, a long and finely graduated

series of transitions leads from bisexual to unisexual blossoms; and so

in various other respects. Everywhere we may perceive that Nature

secures her ends, and makes her distinctions on the whole manifest and

real but everywhere without abrupt breaks We need not wonder therefore

that gradations between species and varieties should occur; the more

so, since genera, tribes, and other groups into which the naturalist

collocates species, are far from being always absolutely limited in

Nature, though they are necessarily represented to be so in systems.

From the necessity of the case, the classifications of the naturalist

abruptly define where Nature more or less blends. Our systems are

nothing, if not definite. They express differences, and some of the

coarser gradations. But this evinces not their perfection, but their

imperfection. Even the best of them are to the system of Nature what

consecutive patches of the seven colors are to the rainbow.

Now the principle of gradation throughout organic Nature may, of

course, be interpreted upon other assumptions than those of Darwins

hypothesis--certainly upon quite other than those of a materialistic

philosophy, with which we ourselves have no sympathy. Still we conceive

it not only possible, but probable, that this gradation, as it has its

natural ground, may yet have its scientific explanation. In any case,

there is no need to deny that the general facts correspond well with an

hypothesis like Darwins, which is built upon fine gradations.

We have contemplated quite long enough the general presumptions in

favor of an hypothesis of the derivation of species. We cannot forget,

however, while for the moment we overlook, the formidable difficulties

which all hypotheses of this class have to encounter, and the serious

implications which they seem to involve. We feel, moreover, that

Darwins particular hypothesis is exposed to some special objections. It

requires no small strength of nerve steadily to conceive, not only of

the diversification, but of the formation of the organs of an animal

through cumulative variation and natural selection. Think of such an

organ as the eye, that most perfect of optical instruments, as so

produced in the lower animals and perfected in the higher! A friend of

ours, who accepts the new doctrine, confesses that for a long while a

cold chill came over him whenever he thought of the eye. He has at

length got over that stage of the complaint, and is now in the fever of

belief, perchance to be succeeded by the sweating stage, during which

sundry peccant humors may be eliminated from the system. For ourselves,

we dread the chill, and have some misgivings about the consequences of

the reaction. We find ourselves in the "singular position"

acknowledged by Pictet--that is, confronted with a theory which,

although it can really explain much, seems inadequate to the heavy task

it so boldly assumes, but which, nevertheless, appears better fitted

than any other that has been broached to explain, if it be possible to

explain, somewhat of the manner in which organized beings may have

arisen and succeeded each other. In this dilemma we might take

advantage of Mr. Darwins candid admission, that he by no means expects

to convince old and experienced people, whose minds are stocked with a

multitude of facts all regarded during a long course of years from the

old point of view. This is nearly our case. So, owning no call to a

larger faith than is expected of us, but not prepared to pronounce the

whole hypothesis untenable, under such construction as we should put

upon it, we naturally sought to attain a settled conviction through a

perusal of several proffered refutations of the theory. At least, this

course seemed to offer the readiest way of bringing to a head the

various objections to which the theory is exposed. On several accounts

some of these opposed reviews especially invite examination. We

propose, accordingly, to conclude our task with an article upon "Darwin

and his Reviewers."