We are not disposed nor prepared to take sides for or against the new

hypothesis, and so, perhaps, occupy a good position from which to watch the

discussion and criticise those objections which are seemingly inconclusive.

On surveying the arguments urged by those who have undertaken to demolish

the theory, we have been most impressed with a sense of their great

inequality. Some strike us as excellent and perhaps unanswerable; some, as

incongruous with other views of the same writers; others, when carried out,

as incompatible with general experience or general beliefs, and therefore

as proving too much; still others, as proving nothing at all; so that, on

the whole, the effect is rather confusing and disappointing. We certainly

expected a stronger adverse case than any which the thoroughgoing opposers

of Darwin appear to have made out. Wherefore, if it be found that the new

hypothesis has grown upon our favor as we proceeded, this must be

attributed not so much to the force of the arguments of the book itself as

to the want of force of several of those by which it has been assailed.

Darwin's arguments we might resist or adjourn; but some of the refutations

of it give us more concern than the book itself did.

These remarks apply mainly to the philosophical and theological objections

which have been elaborately urged, almost exclusively by the American

reviewers. The North British reviewer, indeed, roundly denounces the book

as atheistical, but evidently deems the case too clear for argument. The

Edinburgh reviewer, on the contrary, scouts all such objections--as well he

may, since he records his belief in "a continuous creative operation," a

constantly operating secondary creational law," through which species are

successively produced; and he emits faint, but not indistinct, glimmerings

of a transmutation theory of his own;[III-8] so that he is equally exposed

to all the philosophical objections advanced by Agassiz, and to most of

those urged by the other American critics, against Darwin himself.

Proposing now to criticise the critics, so far as to see what their most

general and comprehensive objections amount to, we must needs begin with

the American reviewers, and with their arguments adduced to prove that a

derivative hypothesis ought not to be true, or is not possible,

philosophical, or theistic.

It must not be forgotten that on former occasions very confident judgments

have been pronounced by very competent persons, which have not been finally

ratified. Of the two great minds of the seventeenth century, Newton and

Leibnitz, both profoundly religious as well as philosophical, one produced

the theory of gravitation, the other objected to that theory that it was

subversive of natural religion. The nebular hypothesis--a natural

consequence of the theory of gravitation and of the subsequent progress of

physical and astronomical discovery--has been denounced as atheistical even

down to our own day. But it is now largely adopted by the most theistical

natural philosophers as a tenable and perhaps sufficient hypothesis, and

where not accepted is no longer objected to, so far as we know, on

philosophical or religious grounds.

The gist of the philosophical objections urged by the two Boston reviewers

against an hypothesis of the derivation of species--or at least against

Darwin's particular hypothesis-- is, that it is incompatible with the idea

of any manifestation of design in the universe, that it denies final

causes. A serious objection this, and one that demands very serious

attention.

The proposition, that things and events in Nature were not designed to be

so, if logically carried out, is doubtless tantamount to atheism. Yet most

people believe that some were designed and others were not, although they

fall into a hopeless maze whenever they undertake to define their position.

So we should not like to stigmatize as atheistically disposed a person who

regards certain things and events as being what they are through designed

laws (whatever that expression means), but as not themselves specially

ordained, or who, in another connection, believes in general, but not in

particular Providence. We could sadly puzzle him with questions; but in

return he might equally puzzle us. Then, to deny that anything was

specially designed to be what it is, is one proposition; while to deny that

the Designer supernaturally or immediately made it so, is another: though

the reviewers appear not to recognize the distinction.

Also, "scornfully to repudiate" or to "sneer at the idea of any

manifestation of design in the material universe,"[III-9] is one thing;

while to consider, and perhaps to exaggerate, the difficulties which attend

the practical application of the doctrine of final causes to certain

instances, is quite another thing: yet the Boston reviewers, we regret to

say, have not been duly regardful of the difference. Whatever be thought of

Darwin's doctrine, we are surprised that he should be charged with scorning

or sneering at the opinions of others, upon such a subject. Perhaps Darwin'

s view is incompatible with final causes--we will consider that question

presently-- but as to the Examiner's charge, that he "sneers at the idea of

any manifestation of design in the material universe," though we are

confident that no misrepresentation was intended, we are equally confident

that it is not at all warranted by the two passages cited in support of it.

Here are the passages:

"If green woodpeckers alone had existed, or we did not know that there were

many black and pied kinds, I dare say that we should have thought that the

green color was a beautiful adaptation to hide this tree-frequenting bird

from its enemies."

"If our reason leads us to admire with enthusiasm a multitude of inimitable

contrivances in Nature, this same reason tells us, though we may easily err

on both sides, that some contrivances are less perfect. Can we consider the

sting of the wasp or of the bee as perfect, which, when used against many

attacking animals, cannot be withdrawn, owing to the backward serratures,

and so inevitably causes the death of the insect by tearing out its

viscera?"

If the sneer here escapes ordinary vision in the detached extracts (one of

them wanting the end of the sentence), it is, if possible, more

imperceptible when read with the context. Moreover, this perusal inclines

us to think that the Examiner has misapprehended the particular argument or

object, as well as the spirit, of the author in these passages. The whole

reads more naturally as a caution against the inconsiderate use of final

causes in science, and an illustration of some of the manifold errors and

absurdities which their hasty assumption is apt to involve--considerations

probably equivalent to those which induced Lord Bacon to liken final causes

to "vestal virgins." So, if any one, it is here Bacon that "sitteth in the

seat of the scornful." As to Darwin, in the section from which the extracts

were made, he is considering a subsidiary question, and trying to obviate a

particular difficulty, but, we suppose, is wholly unconscious of denying

"any manifestation of design in the material universe." He concludes the

first sentence:

--"and consequently that it was a character of importance, and might have

been acquired through natural selection; as it is, I have no doubt that the

color is due to some quite distinct cause, probably to sexual selection."

After an illustration from the vegetable creation, Darwin adds:

"The naked skin on the head of a vulture is generally looked at as a direct

adaptation for wallowing in putridity; and so it may be, or it may possibly

be due to the direct action of putrid matter; but we should be very

cautious in drawing any such inference, when we see that the skin on the

head of the clean-feeding male turkey is likewise naked. The sutures in the

skulls of young mammals have been advanced as a beautiful adaptation for

aiding parturition, and no doubt they facilitate or may be indispensable

for this act; but as sutures occur in the skulls of young birds and

reptiles, which have only to escape from a broken egg, we may infer that

this structure has arisen from the laws of growth, and has been taken

advantage of in the parturition of the higher animals."

All this, simply taken, is beyond cavil, unless the attempt to explain

scientifically how any designed result is accomplished savors of

impropriety.

In the other place, Darwin is contemplating the patent fact that

"perfection here below" is relative, not absolute--and illustrating this by

the circumstance that European animals, and especially plants, are now

proving to be better adapted for New Zealand than many of the indigenous

ones--that "the correction for the aberration of light is said, on high

authority, not to be quite perfect even in that most perfect organ, the

eye." And then follows the second extract of the reviewer. But what is the

position of the reviewer upon his own interpretation of these passages? If

he insists that green woodpeckers were specifically created so in order

that they might be less liable to capture, must he not equally hold that

the black and pied ones were specifically made of these colors in order

that they might be more liable to be caught? And would an explanation of the

mode in which those woodpeckers came to be green, however complete,

convince him that the color was undesigned?

As to the other illustration, is the reviewer so complete an optimist as to

insist that the arrangement and the weapon are wholly perfect (quoad the

insect) the normal use of which often causes the animal fatally to injure

or to disembowel itself? Either way it seems to us that the argument here,

as well as the insect, performs hari-kari. The Examiner adds:

"We should in like manner object to the word favorable, as implying that

some species are placed by the Creator under unfavorable circumstances, at

least under such as might be advantageously modified."

But are not many individuals and some races of men placed by the Creator

"under unfavorable circumstances, at least under such as might be

advantageously modified?" Surely these reviewers must be living in an ideal

world, surrounded by "the faultless monsters which our world ne'er saw," in

some elysium where imperfection and distress were never heard of! Such

arguments resemble some which we often hear against the Bible, holding that

book responsible as if it originated certain facts on the shady side of

human nature or the apparently darker lines of Providential dealing, though

the facts are facts of common observation and have to be confronted upon

any theory.

The North American reviewer also has a world of his own--just such a one as

an idealizing philosopher would be apt to devise--that is, full of sharp

and absolute distinctions: such, for instance, as the "absolute

invariableness of instinct;" an absolute want of intelligence in any brute

animal; and a complete monopoly of instinct by the brute animals, so that

this "instinct is a great matter" for them only, since it sharply and

perfectly distinguishes this portion of organic Nature from the vegetable

kingdom on the one hand and from man on the other: most convenient views for

argumentative purposes, but we suppose not borne out in fact.

In their scientific objections the two reviewers take somewhat different

lines; but their philosophical and theological arguments strikingly

coincide. They agree in emphatically asserting that Darwin's hypothesis of

the origination of species through variation and natural selection

"repudiates the whole doctrine of final causes," and "all indication of

design or purpose in the organic world . . . is neither more nor less than

a formal denial of any agency beyond that of a blind chance in the

developing or perfecting of the organs or instincts of created beings. . .

. It is in vain that the apologists of this hypothesis might say that it

merely attributes a different mode and time to the Divine agency--that all

the qualities subsequently appearing in their descendants must have been

implanted, and have remained latent in the original pair." Such a view, the

Examiner declares, "is nowhere stated in this book, and would be, we are

sure, disclaimed by the author."

We should like to be informed of the grounds of this sureness. The marked

rejection of spontaneous generation--the statement of a belief that all

animals have descended from four or five progenitors, and plants from an

equal or lesser number, or, perhaps, if constrained to it by analogy, "from

some one primordial form into which life was first breathed"--coupled with

the expression, "To my mind it accords better with what we know of the laws

impressed on matter by the Creator, that the production and extinction of

the past and present inhabitants of the world should have been due to

secondary causes," than "that each species has been independently

created"--these and similar expressions lead us to suppose that the author

probably does accept the kind of view which the Examiner is sure he would

disclaim. At least, we charitably see nothing in his scientific theory to

hinder his adoption of Lord Bacon's "Confession of Faith" in this regard--

"That, notwithstanding God hath rested and ceased from creating, yet,

nevertheless, he doth accomplish and fulfill his divine will in all things,

great and small, singular and general, as fully and exactly by providence

as he could by miracle and new creation, though his working be not

immediate and direct, but by compass; not violating Nature, which is his

own law upon the creature."

However that may be, it is undeniable that Mr. Darwin has purposely been

silent upon the philosophical and theological applications of his theory.

This reticence, under the circumstances, argues design, and raises inquiry

as to the final cause or reason why. Here, as in higher instances,

confident as we are that there is a final cause, we must not be

overconfident that we can infer the particular or true one. Perhaps the

author is more familiar with natural-historical than with philosophical

inquiries, and, not having decided which particular theory about efficient

cause is best founded, he meanwhile argues the scientific questions

concerned--all that relates to secondary causes--upon purely scientific

grounds, as he must do in any case. Perhaps, confident, as he evidently is,

that his view will finally be adopted, he may enjoy a sort of satisfaction

in hearing it denounced as sheer atheism by the inconsiderate, and

afterward, when it takes its place with the nebular hypothesis and the

like, see this judgment reversed, as we suppose it would be in such event.

Whatever Mr. Darwin's philosophy may be, or whether he has any, is a matter

of no consequence at all, compared with the important questions, whether a

theory to account for the origination and diversification of animal and

vegetable forms through the operation of secondary causes does or does not

exclude design; and whether the establishment by adequate evidence of

Darwin's particular theory of diversification through variation and natural

selection would essentially alter the present scientific and philosophical

grounds for theistic views of Nature. The unqualified affirmative judgment

rendered by the two Boston reviewers, evidently able and practised

reasoners, "must give us pause." We hesitate to advance our conclusions in

opposition to theirs. But, after full and serious consideration, we are

constrained to say that, in our opinion, the adoption of a derivative

hypothesis, and of Darwin's particular hypothesis, if we understand it,

would leave the doctrines of final causes, utility, and special design,

just where they were before. We do not pretend that the subject is not

environed with difficulties. Every view is so environed; and every shifting

of the view is likely, if it removes some difficulties, to bring others

into prominence. But we cannot perceive that Darwin's theory brings in any

new kind of scientific difficulty, that is, any with which philosophical

naturalists were not already familiar.

Since natural science deals only with secondary or natural causes, the

scientific terms of a theory of derivation of species--no less than of a

theory of dynamics--must needs be the same to the theist as to the atheist.

The difference appears only when the inquiry is carried up to the question

of primary cause--a question which belongs to philosophy. Wherefore, Darwin

's reticence about efficient cause does not disturb us. He considers only

the scientific questions. As already stated, we think that a theistic view

of Nature is implied in his book, and we must charitably refrain from

suggesting the contrary until the contrary is logically deduced from his

premises. If, however, he anywhere maintains that the natural causes

through which species are diversified operate without an ordaining and

directing intelligence, and that the orderly arrangements and admirable

adaptations we see all around us are fortuitous or blind, undesigned

results--that the eye, though it came to see, was not designed for seeing,

nor the hand for handling--then, we suppose, he is justly chargeable with

denying, and very needlessly denying, all design in organic Nature;

otherwise, we suppose not. Why, if Darwin's well-known passage about the

eye[III-10] equivocal though some of the language be--does not imply

ordaining and directing intelligence, then he refutes his own theory as

effectually as any of his opponents are likely to do. He asks:

"May we not believe that [under variation proceeding long enough,

generation multiplying the better variations times enough, and natural

selection securing the improvements] a living optical instrument might be

thus formed as superior to one of glass as the works of the Creator are to

those of man?"

This must mean one of two things: either that the living instrument was

made and perfected under (which is the same thing as by) an intelligent

First Cause, or that it was not. If it was, then theism is asserted; and as

to the mode of operation, how do we know, and why must we believe, that,

fitting precedent forms being in existence, a living instrument (so

different from a lifeless manufacture) would be originated and perfected in

any other way, or that this is not the fitting way? If it means that it was

not, if he so misuses words that by the Creator he intends an unintelligent

power, undirected force, or necessity, then he has put his case so as to

invite disbelief in it. For then blind forces have produced not only

manifest adaptions of means to specific ends--which is absurd enough--but

better adjusted and more perfect instruments or machines than intellect

(that is, human intellect) can contrive and human skill execute--which no

sane person will believe.

On the other hand, if Darwin even admits--we will not say adopts--the

theistic view, he may save himself much needless trouble in the endeavor to

account for the absence of every sort of intermediate form. Those in the

line between one species and another supposed to be derived from it he may

be bound to provide; but as to "an infinite number of other varieties not

intermediate, gross, rude, and purposeless, the unmeaning creations of an

unconscious cause," born only to perish, which a relentless reviewer has

imposed upon his theory--rightly enough upon the atheistic alternative--the

theistic view rids him at once of this "scum of creation." For, as species

do not now vary at all times and places and in all directions, nor produce

crude, vague, imperfect, and useless forms, there is no reason for

supposing that they ever did. Good-for-nothing monstrosities, failures of

purpose rather than purposeless, indeed, sometimes occur; but these are just

as anomalous and unlikely upon Darwin's theory as upon any other. For his

particular theory is based, and even over-strictly insists, upon the most

universal of physiological laws, namely, that successive generations shall

differ only slightly, if at all, from their parents; and this effectively

excludes crude and impotent forms. Wherefore, if we believe that the

species were designed, and that natural propagation was designed, how can

we say that the actual varieties of the species were not equally designed?

Have we not similar grounds for inferring design in the supposed varieties

of species, that we have in the case of the supposed species of a genus?

When a naturalist comes to regard as three closely related species what

he before took to be so many varieties of one species how has he thereby

strengthened our conviction that the three forms are designed to have

the differences which they actually exhibit? Wherefore so long as

gradatory, orderly, and adapted forms in Nature argue design, and at

least while the physical cause of variation is utterly unknown and

mysterious, we should advise Mr. Darwin to assume in the philosophy of

his hypothesis that variation has been led along certain beneficial

lines. Streams flowing over a sloping plain by gravitation (here the

counterpart of natural selection) may have worn their actual channels as

they flowed; yet their particular courses may have been assigned; and

where we see them forming definite and useful lines of irrigation, after

a manner unaccountable on the laws of gravitation and dynamics, we

should believe that the distribution was designed.

To insist, therefore, that the new hypothesis of the derivative origin of

the actual species is incompatible with final causes and design, is to take

a position which we must consider philosophically untenable. We must also

regard it as highly unwise and dangerous, in the present state and present

prospects of physical and physiological science. We should expect the

philosophical atheist or skeptic to take this ground; also, until better

informed, the unlearned and unphilosophical believer; but we should think

that the thoughtful theistic philosopher would take the other side. Not to

do so seems to concede that only supernatural events can be shown to be

designed, which no theist can admit--seems also to misconceive the scope

and meaning of all ordinary arguments for design in Nature. This

misconception is shared both by the reviewers and the reviewed. At least,

Mr. Darwin uses expressions which imply that the natural forms which

surround us, because they have a history or natural sequence, could have

been only generally, but not particularly designed--a view at once

superficial and contradictory; whereas his true line should be, that his

hypothesis concerns the order and not the cause, the how and not the why of

the phenomena, and so leaves the question of design just where it was

before.

To illustrate this from the theist's point of view: Transfer the question

for a moment from the origination of species to the origination of

individuals, which occurs, as we say, naturally. Because natural, that is,

"stated, fixed, or settled," is it any the less designed on that account?

We acknowledge that God is our maker--not merely the originator of the

race, but our maker as individuals--and none the less so because it pleased

him to make us in the way of ordinary generation. If any of us were born

unlike our parents and grandparents, in a slight degree, or in whatever

degree, would the case be altered in this regard?

The whole argument in natural theology proceeds upon the ground that the

inference for a final cause of the structure of the hand and of the valves

in the veins is just as valid now, in individuals produced through natural

generation, as it would have been in the case of the first man,

supernaturally created. Why not, then, just as good even on the supposition

of the descent of men from chimpanzees and gorillas, since those animals

possess these same contrivances? Or, to take a more supposable case: If the

argument from structure to design is convincing when drawn from a particular

animal, say a Newfoundland dog, and is not weakened by the knowledge that

this dog came from similar parents, would it be at all weakened if, in

tracing his genealogy, it were ascertained that he was a remote descendant

of the mastiff or some other breed, or that both these and other breeds

came (as is suspected) from some wolf? If not, how is the argument for

design in the structure of our particular dog affected by the supposition

that his wolfish progenitor came from a post-tertiary wolf, perhaps less

unlike an existing one than the dog in question is to some other of the

numerous existing races of dogs, and that this post-tertiary came from an

equally or more different tertiary wolf? And if the argument from structure

to design is not invalidated by our present knowledge that our

individual dog was developed from a single organic cell, how is it

invalidated by the supposition of an analogous natural descent, through a

long line of connected forms, from such a cell, or from some simple animal,

existing ages before there were any dogs?

Again, suppose we have two well-known and apparently most decidedly

different animals or plants, A and D, both presenting, in their structure

and in their adaptations to the conditions of existence, as valid and clear

evidence of design as any animal or plant ever presented: suppose we have

now discovered two intermediate species, B and C, which make up a series

with equable differences from A to D. Is the proof of design or final cause

in A and D, whatever it amounted to, at all weakened by the discovery of the

intermediate forms? Rather does not the proof extend to the intermediate

species, and go to show that all four were equally designed? Suppose, now,

the number of intermediate forms to be much increased, and therefore the

gradations to be closer yet--as close as those between the various sorts of

dogs, or races of men, or of horned cattle: would the evidence of design,

as shown in the structure of any of the members of the series, be any

weaker than it was in the case of A and D? Whoever contends that it would

be, should likewise maintain that the origination of individuals by

generation is incompatible with design, or an impossibility in Nature. We

might all have confidently thought the latter, antecedently to experience

of the fact of reproduction. Let our experience teach us wisdom.

These illustrations make it clear that the evidence of design from

structure and adaptation is furnished complete by the individual animal or

plant itself, and that our knowledge or our ignorance of the history of its

formation or mode of production adds nothing to it and takes nothing away.

We infer design from certain arrangements and results; and we have no other

way of ascertaining it. Testimony, unless infallible, cannot prove it, and

is out of the question here. Testimony is not the appropriate proof of

design: adaptation to purpose is. Some arrangements in Nature appear to be

contrivances, but may leave us in doubt. Many others, of which the eye and

the hand are notable examples, compel belief with a force not appreciably

short of demonstration. Clearly to settle that such as these must have been

designed goes far toward proving that other organs and other seemingly less

explicit adaptations in Nature must also have been designed, and clinches

our belief, from manifold considerations, that all Nature is a preconcerted

arrangement, a manifested design. A strange contradiction would it be to

insist that the shape and markings of certain rude pieces of flint, lately

found in drift-deposits, prove design, but that nicer and thousand-fold

more complex adaptations to use in animals and vegetables do not a fortiori

argue design.

We could not affirm that the arguments for design in Nature are conclusive

to all minds. But we may insist, upon grounds already intimated, that,

whatever they were good for before Darwin's book appeared, they are good

for now. To our minds the argument from design always appeared conclusive

of the being and continued operation of an intelligent First Cause, the

Ordainer of Nature; and we do not see that the grounds of such belief would

be disturbed or shifted by the adoption of Darwin's hypothesis. We are not

blind to the philosophical difficulties which the thoroughgoing implication

of design in Nature has to encounter, nor is it our vocation to obviate

them It suffices us to know that they are not new nor peculiar

difficulties--that, as Darwin's theory and our reasonings upon it did not

raise these perturbing spirits, they are not bound to lay them. Meanwhile,

that the doctrine of design encounters the very same difficulties in the

material that it does in the moral world is Just what ought to be expected.

So the issue between the skeptic and the theist is only the old one, long

ago argued out--namely, whether organic Nature is a result of design or of

chance. Variation and natural selection open no third alternative; they

concern only the question how the results, whether fortuitous or designed,

may have been brought about. Organic Nature abounds with unmistakable and

irresistible indications of design, and, being a connected and consistent

system, this evidence carries the implication of design throughout the

whole. On the other hand, chance carries no probabilities with it, can never

be developed into a consistent system, but, when applied to the explanation

of orderly or beneficial results, heaps up improbabilities at every step

beyond all computation. To us, a fortuitous Cosmos is simply inconceivable.

The alternative is a designed Cosmos.

It is very easy to assume that, because events in Nature are in one sense

accidental, and the operative forces which bring them to pass are themselves

blind and unintelligent (physically considered, all forces are), therefore

they are undirected, or that he who describes these events as the results

of such forces thereby assumes that they are undirected. This is the

assumption of the Boston reviewers, and of Mr. Agassiz, who insists that

the only alternative to the doctrine, that all organized beings were

supernaturally created just as they are, is, that they have arisen

spontaneously through the omnipotence of matter.[III-11]

As to all this, nothing is easier than to bring out in the conclusion what

you introduce in the premises. If you import atheism into your conception

of variation and natural selection, you can readily exhibit it in the

result. If you do not put it in, perhaps there need be none to come out.

While the mechanician is considering a steamboat or locomotive-engine as a

material organism, and contemplating the fuel, water, and steam, the source

of the mechanical forces, and how they operate, he may not have occasion to

mention the engineer. But, the orderly and special results accomplished, the

why the movements are in this or that particular direction, etc., is

inexplicable without him. If Mr. Darwin believes that the events which he

supposes to have occurred and the results we behold were undirected and

undesigned, or if the physicist believes that the natural forces to which

he refers phenomena are uncaused and undirected, no argument is needed to

show that such belief is atheism. But the admission of the phenomena and of

these natural processes and forces does not necessitate any such belief, nor

even render it one whit less improbable than before.

Surely, too, the accidental element may play its part in Nature without

negativing design in the theist's view. He believes that the earth's surface

has been very gradually prepared for man and the existing animal races,

that vegetable matter has through a long series of generations imparted

fertility to the soil in order that it may support its present occupants,

that even beds of coal have been stored up for man's benefit Yet what is

more accidental, and more simply the consequence of physical agencies than

the accumulation of vegetable matter in a peat bog and its transformation

into coal? No scientific person at this day doubts that our solar system is

a progressive development, whether in his conception he begins with molten

masses, or aeriform or nebulous masses, or with a fluid revolving mass of

vast extent, from which the specific existing worlds have been developed

one by one What theist doubts that the actual results of the development in

the inorganic worlds are not merely compatible with design but are in the

truest sense designed re suits? Not Mr. Agassiz, certainly, who adopts a

remarkable illustration of design directly founded on the nebular hypothesis

drawing from the position and times of the revolution of the world, so

originated direct evidence that the physical world has been ordained in

conformity with laws which obtain also among living beings But the reader

of the interesting exposition[III-12] will notice that the designed result

has been brought to pass through what, speaking after the manner of men,

might be called a chapter of accidents.

A natural corollary of this demonstration would seem to be, that a material

connection between a series of created things--such as the development of

one of them from another, or of all from a common stock--is highly

compatible with their intellectual connection, namely, with their being

designed and directed by one mind. Yet upon some ground which is not

explained, and which we are unable to conjecture, Mr. Agassiz concludes to

the contrary in the organic kingdoms, and insists that, because the members

of such a series have an intellectual connection, "they cannot be the result

of a material differentiation of the objects themselves,"[III-13] that is,

they cannot have had a genealogical connection. But is there not as much

intellectual connection between the successive generations of any species

as there is between the several species of a genus, or the several genera

of an order? As the intellectual connection here is realized through the

material connection, why may it not be so in the case of species and genera?

On all sides, therefore, the implication seems to be quite the other way.

Returning to the accidental element, it is evident that the strongest point

against the compatibility of Darwin's hypothesis with design in Nature is

made when natural selection is referred to as picking out those variations

which are improvements from a vast number which are not improvements, but

perhaps the contrary, and therefore useless or purposeless, and born to

perish. But even here the difficulty is not peculiar; for Nature abounds

with analogous instances. Some of our race are useless, or worse, as

regards the improvement of mankind; yet the race may be designed to improve,

and may be actually improving. Or, to avoid the complication with free

agency--the whole animate life of a country depends absolutely upon the

vegetation, the vegetation upon the rain. The moisture is furnished by the

ocean, is raised by the sun's heat from the ocean's surface, and is wafted

inland by the winds. But what multitudes of raindrops fall back into the

ocean--are as much without a final cause as the incipient varieties which

come to nothing! Does it therefore follow that the rains which are bestowed

upon the soil with such rule and average regularity were not designed to

support vegetable and animal life? Consider, likewise, the vast proportion

of seeds and pollen, of ova and young--a thousand or more to one--which

come to nothing, and are therefore purposeless in the same sense, and only

in the same sense, as are Darwin's unimproved and unused slight variations.

The world is full of such cases; and these must answer the argument--for we

cannot, except by thus showing that it proves too much.

Finally, it is worth noticing that, though natural selection is

scientifically explicable, variation is not. Thus far the cause of

variation, or the reason why the offspring is sometimes unlike the parents,

is just as mysterious as the reason why it is generally like the parents.

It is now as inexplicable as any other origination; and, if ever explained,

the explanation will only carry up the sequence of secondary causes one

step farther, and bring us in face of a somewhat different problem, but

which will have the same element of mystery that the problem of variation

has now. Circumstances may preserve or may destroy the variations man may

use or direct them but selection whether artificial or natural no more

originates them than man originates the power which turns a wheel when he

dams a stream and lets the water fall upon it The origination of this power

is a question about efficient cause. The tendency of science in respect to

this obviously is not toward the omnipotence of matter, as some suppose,

but to ward the omnipotence of spirit.

So the real question we come to is as to the way in which we are to

conceive intelligent and efficient cause to be exerted, and upon what

exerted. Are we bound to suppose efficient cause in all cases exerted upon

nothing to evoke something into existence--and this thousands of times

repeated, when a slight change in the details would make all the difference

between successive species? Why may not the new species, or some of them,

be designed diversifications of the old?

There are, perhaps, only three views of efficient cause which may claim to

be both philosophical and theistic:

1. The view of its exertion at the beginning of time, endowing matter and

created things with forces which do the work and produce the phenomena.

2. This same view, with the theory of insulated interpositions, or

occasional direct action, engrafted upon it--the view that events and

operations in general go on in virtue simply of forces communicated at the

first, but that now and then, and only now and then, the Deity puts his

hand directly to the work.

3. The theory of the immediate, orderly, and constant, however infinitely

diversified, action of the intelligent efficient Cause.

It must be allowed that, while the third is preeminently the Christian

view, all three are philosophically compatible with design in Nature. The

second is probably the popular conception. Perhaps most thoughtful people

oscillate from the middle view toward the first or the third--adopting the

first on some occasions, the third on others. Those philosophers who like

and expect to settle all mooted questions will take one or the other

extreme. The Examiner inclines toward, the North American reviewer fully

adopts, the third view, to the logical extent of maintaining that "the

origin of an individual, as well as the origin of a species or a genus, can

be explained only by the direct action of an intelligent creative cause."

To silence his critics, this is the line for Mr. Darwin to take; for it at

once and completely relieves his scientific theory from every theological

objection which his reviewers have urged against it.

At present we suspect that our author prefers the first conception,

though he might contend that his hypothesis is compatible with either of

the three. That it is also compatible with an atheistic or pantheistic

conception of the universe, is an objection which, being shared by all

physical, and some ethical or moral science, cannot specially be urged

against Darwin's system. As he rejects spontaneous generation, and admits of

intervention at the beginning of organic life, and probably in more than one

instance, he is not wholly excluded from adopting the middle view, although

the interventions he would allow are few and far back. Yet one

interposition admits the principle as well as more. Interposition

presupposes particular necessity or reason for it, and raises the question,

when and how often it may have been necessary. It might be the natural

supposition, if we had only one set of species to account for, or if the

successive inhabitants of the earth had no other connections or

resemblances than those which adaptation to similar conditions, which final

causes in the narrower sense, might explain. But if this explanation of

organic Nature requires one to "believe that, at innumerable periods in the

earth's history, certain elemental atoms have been commanded suddenly to

flash into living tissues," and this when the results are seen to be

strictly connected and systematic, we cannot wonder that such interventions

should at length be considered, not as interpositions or interferences, but

rather--to use the reviewer's own language--as "exertions so frequent and

beneficent that we come to regard them as the ordinary action of Him who

laid the foundation of the earth, and without whom not a sparrow falleth to

the ground."[III-14] What does the difference between Mr. Darwin and his

reviewer now amount to? If we say that according to one view the

origination of species is natural, according to the other miraculous, Mr.

Darwin agrees that "what is natural as much requires and presupposes an

intelligent mind to render it so-- that is, to effect it continually or at

stated times--as what is supernatural does to effect it for once."[III-15]

He merely inquires into the form of the miracle, may remind us that all

recorded miracles (except the primal creation of matter) were

transformations or actions in and upon natural things, and will ask how

many times and how frequently may the origination of successive species be

repeated before the supernatural merges in the natural.

In short, Darwin maintains that the origination of a species, no less than

that of an individual, is natural; the reviewer, that the natural

origination of an individual, no less than the origination of a species,

requires and presupposes Divine power. A fortiori, then, the origination of

a variety requires and presupposes Divine power. And so between the

scientific hypothesis of the one and the philosophical conception of the

other no contrariety remains. And so, concludes the North American

reviewer, "a proper view of the nature of causation places the vital

doctrine of the being and the providence of a God on ground that can never

be shaken."[III-16] A worthy conclusion, and a sufficient answer to the

denunciations and arguments of the rest of the article, so far as

philosophy and natural theology are concerned. If a writer must needs use

his own favorite dogma as a weapon with which to give coup de grace to a

pernicious theory, he should be careful to seize his edge-tool by the

handle, and not by the blade.

We can barely glance at a subsidiary philosophical objection of the North

American reviewer, which the Examiner also raises, though less explicitly.

Like all geologists, Mr. Darwin draws upon time in the most unlimited

manner. He is not peculiar in this regard. Mr. Agassiz tells us that the

conviction is "now universal, among well-informed naturalists, that this

globe has been in existence for innumerable ages, and that the length of

time elapsed since it first became inhabited cannot be counted in years;"

Pictet, that the imagination refuses to calculate the immense number of

years and of ages during which the faunas of thirty or more epochs have

succeeded one another, and developed their long succession of generations.

Now, the reviewer declares that such indefinite succession of ages is

"virtually infinite," "lacks no characteristic of eternity except its

name," at least, that "the difference between such a conception and that of

the strictly infinite, if any, is not appreciable." But infinity belongs to

metaphysics. Therefore, he concludes, Darwin supports his theory, not by

scientific but by metaphysical evidence; his theory is "essentially and

completely metaphysical in character, resting altogether upon that idea of

'the infinite' which the human mind can neither put aside nor

comprehend."[III-17] And so a theory which will be generally regarded as

much too physical is transferred by a single syllogism to metaphysics.

Well, physical geology must go with it: for, even on the soberest view, it

demands an indefinitely long time antecedent to the introduction of organic

life upon our earth. A fortiori is physical astronomy a branch of

metaphysics, demanding, as it does, still larger "instalments of infinity,"

as the reviewer calls them, both as to time and number. Moreover, far the

greater part of physical inquiries now relate to molecular actions, which,

a distinguished natural philosopher informs us, "we have to regard as the

results of an infinite number of in finitely small material particles,

acting on each other at infinitely small distances"--a triad of

infinities--and so physics becomes the most metaphysical of sciences.

Verily, if this style of reasoning is to prevail--

"Thinking is but an idle waste of thought,

And naught is everything, and everything is naught."

The leading objection of Mr. Agassiz is likewise of a philosophical

character. It is, that species exist only "as categories of thought"--that,

having no material existence, they can have had no material variation, and

no material community of origin. Here the predication is of species in the

subjective sense, the inference in the objective sense. Reduced to plain

terms, the argument seems to be: Species are ideas; therefore the objects

from which the idea is derived cannot vary or blend, and cannot have had a

genealogical connection.

The common view of species is, that, although they are generalizations, yet

they have a direct objective ground in Nature, which genera, orders, etc.,

have not. According to the succinct definition of Jussieu--and that of

Linnaeus is identical in meaning--a species is the perennial succession of

similar individuals in continued generations. The species is the chain of

which the individuals are the links. The sum of the

genealogically-connected similar individuals constitutes the species, which

thus has an actuality and ground of distinction not shared by genera and

other groups which were not supposed to be genealogically connected. How a

derivative hypothesis would modify this view, in assigning to species only

a temporary fixity, is obvious. Yet, if naturalists adopt that hypothesis,

they will still retain Jussieu's definition, which leaves untouched the

question as to how and when the "perennial successions" were established.

The practical question will only be, How much difference between two sets of

individuals entitles them to rank under distinct species? and that is the

practical question now, on whatever theory. The theoretical question is--as

stated at the beginning of this article--whether these specific lines were

always as distinct as now.

Mr. Agassiz has "lost no opportunity of urging the idea that, while species

have no material existence, they yet exist as categories of thought in the

same way [and only in the same way] as genera, families, orders, classes,"

etc. He

"has taken the ground that all the natural divisions in the animal kingdom

are primarily distinct, founded upon different categories of characters,

and that all exist in the same way, that is, as categories of thought,

embodied in individual living forms. I have attempted to show that branches

in the animal kingdom are founded upon different plans of structure, and

for that very reason have embraced from the beginning representatives

between which there could be no community of origin; that classes are

founded upon different modes of execution of these plans, and therefore

they also embrace representatives which could have no community of origin;

that orders represent the different degrees of complication in the mode of

execution of each class, and therefore embrace representatives which could

not have a community of origin any more than the members of different

classes or branches; that families are founded upon different patterns of

form, and embrace, representatives equally independent in their origin; that

genera are founded upon ultimate peculiarities of structure, embracing

representatives which, from the very nature of their peculiarities, could

have no community of origin; and that, finally, species are based upon

relations--and proportions that exclude, as much as all the preceding

distinctions, the idea of a common descent.

"As the community of characters among the beings belonging to these

different categories arises from the intellectual connection which shows

them to be categories of thought, they cannot be the result of a gradual

material differentiation of the objects themselves. The argument on which

these views are founded may be summed up in the following few words:

Species, genera, families, etc., exist as thoughts, individuals as

facts."[III-18]

An ingenious dilemma caps the argument:

"It seems to me that there is much confusion of ideas in the general

statement of the variability of species so often repeated lately. If

species do not exist at all, as the supporters of the transmutation theory

maintain, how can they vary? And if individuals alone exist, how can the

differences which may be observed among them prove the variability of

species?"

Now, we imagine that Mr. Darwin need not be dangerously gored by either

horn of this curious dilemma. Although we ourselves cherish old-fashioned

prejudices in favor of the probable permanence, and therefore of a more

stable objective ground of species, yet we agree--and Mr. Darwin will agree

fully with Mr. Agassiz--that species, and he will add varieties, "exist as

categories of thought," that is, as cognizable distinctions--which is all

that we can make of the phrase here, whatever it may mean in the

Aristotelian metaphysics. Admitting that species are only categories of

thought, and not facts or things, how does this prevent the individuals,

which are material things, from having varied in the course of time, so as

to exemplify the present almost innumerable categories of thought, or

embodiments of Divine thought in material forms, or--viewed on the human

side--in forms marked with such orderly and graduated resemblances and

differences as to suggest to our minds the idea of species, genera, orders,

etc., and to our reason the inference of a Divine Original? We have no

clear idea how Mr. Agassiz intends to answer this question, in saying that

branches are founded upon different plans of structure, classes upon

different mode of execution of these plans, orders on different degrees of

complication in the mode of execution, families upon different patterns of

form, genera upon ultimate peculiarities of structure, and species upon

relations and proportions. That is, we do not perceive how these several

"categories of thought" exclude the possibility or the probability that the

individuals which manifest or suggest the thoughts had an ultimate

community of origin.

Moreover, Mr. Darwin might insinuate that the particular philosophy of

classification upon which this whole argument reposes is as purely

hypothetical and as little accepted as is his own doctrine. If both are

pure hypotheses, it is hardly fair or satisfactory to extinguish the one by

the other. If there is no real contradiction between them, nothing is

gained by the attempt.

As to the dilemma propounded, suppose we try it upon that category of

thought which we call chair. This is a genus, comprising a common chair

(Sella vulgaris), arm or easy chair (S. cathedra), the rocking-chair (S.

oscillans)--widely distributed in the United States--and some others, each

of which has sported, as the gardeners say, into many varieties. But now,

as the genus and the species have no material existence, how can they vary?

If only individual chairs exist, how can the differences which may be

observed among them prove the variability of the species? To which we reply

by asking, Which does the question refer to, the category of thought, or

the individual embodiment? If the former, then we would remark that our

categories of thought vary from time to time in the readiest manner. And,

although the Divine thoughts are eternal, yet they are manifested to us in

time and succession, and by their manifestation only can we know them, how

imperfectly! Allowing that what has no material existence can have had no

material connection or variation, we should yet infer that what has

intellectual existence and connection might have intellectual variation;

and, turning to the individuals, which represent the species, we do not see

how all this shows that they may not vary. Observation shows us that they

do. Wherefore, taught by fact that successive individuals do vary, we

safely infer that the idea must have varied, and that this variation of the

individual representatives proves the variability of the species, whether

objectively or subjectively regarded.

Each species or sort of chair, as we have said, has its varieties, and one

species shades off by gradations into another. And--note it well--these

numerous and successively slight variations and gradations, far from

suggesting an accidental origin to chairs and to their forms, are very

proofs of design.

Again, edifice is a generic category of thought. Egyptian, Grecian,

Byzantine, and Gothic buildings are well-marked species, of which each

individual building of the sort is a material embodiment. Now, the question

is, whether these categories or ideas may not have been evolved, one from

another in succession, or from some primal, less specialized, edificial

category. What better evidence for such hypothesis could we have than the

variations and grades which connect these species with each other? We might

extend the parallel, and get some good illustrations of natural selection

from the history of architecture, and the origin of the different styles

under different climates and conditions. Two considerations may qualify or

limit the comparison. One, that houses do not propagate, so as to produce

continuing lines of each sort and variety; but this is of small moment on

Agassiz's view, he holding that genealogical connection is not of the

essence of a species at all. The other, that the formation and development

of the ideas upon which human works proceed are gradual; or, as the same

great naturalist well states it, "while human thought is consecutive,

Divine thought is simultaneous." But we have no right to affirm this of

Divine action.

We must close here. We meant to review some of the more general scientific

objections which we thought not altogether tenable. But, after all, we are

not so anxious just now to know whether the new theory is well founded on

facts, as whether it would be harmless if it were. Besides, we feel quite

unable to answer some of these objections, and it is pleasanter to take up

those which one thinks he can.

Among the unanswerable, perhaps the weightiest of the objections, is that

of the absence, in geological deposits, of vestiges of the intermediate

forms which the theory requires to have existed. Here all that Mr. Darwin

can do is to insist upon the extreme imperfection of the geological record

and the uncertainty of negative evidence. But, withal, he allows the force

of the objection almost as much as his opponents urge it--so much so,

indeed, that two of his English critics turn the concession unfairly upon

him, and charge him with actually basing his hypothesis upon these and

similar difficulties--as if he held it because of the difficulties, and not

in spite of them; a handsome return for his candor!

As to this imperfection of the geological record, perhaps we should get a

fair and intelligible illustration of it by imagining the existing animals

and plants of New England, with all their remains and products since the

arrival of the Mayflower, to be annihilated; and that, in the coming time,

the geologists of a new colony, dropped by the New Zealand fleet on its way

to explore the ruins of London, undertake, after fifty years of

examination, to reconstruct in a catalogue the flora and fauna of our day,

that is, from the close of the glacial period to the present time. With all

the advantages of a surface exploration, what a beggarly account it would

be! How many of the land animals and plants which are enumerated in the

Massachusetts official reports would it be likely to contain?

Another unanswerable question asked by the Boston reviewers is, Why, when

structure and instinct or habit vary-- as they must have varied, on Darwin's

hypothesis--they vary together and harmoniously, instead of vaguely? We

cannot tell, because we cannot tell why either varies at all. Yet, as they

both do vary in successive generations--as is seen under domestication--and

are correlated, we can only adduce the fact. Darwin may be precluded from

our answer, but we may say that they vary together because designed to do

so. A reviewer says that the chance of their varying together is

inconceivably small; yet, if they do not, the variant individuals must all

perish. Then it is well that it is not left to chance. To refer to a

parallel case: before we were born, nourishment and the equivalent to

respiration took place in a certain way. But the moment we were ushered

into this breathing world, our actions promptly conformed, both as to

respiration and nourishment, to the before unused structure and to the new

surroundings.

"Now," says the Examiner, "suppose, for instance, the gills of an aquatic

animal converted into lungs, while instinct still compelled a continuance

under water, would not drowning ensue?" No doubt. But--simply contemplating

the facts, instead of theorizing--we notice that young frogs do not keep

their heads under water after ceasing to be tadpoles. The instinct promptly

changes with the structure, without supernatural interposition--just as

Darwin would have it, if the development of a variety or incipient species,

though rare, were as natural as a metamorphosis.

"Or if a quadruped, not yet furnished with wings, were suddenly inspired

with the instinct of a bird, and precipitated itself from a cliff, would

not the descent be hazardously rapid?" Doubtless the animal would be no

better supported than the objection. But Darwin makes very little indeed of

voluntary efforts as a cause of change, and even poor Lamarck need not be

caricatured. He never supposed that an elephant would take such a notion

into his wise head, or that a squirrel would begin with other than short and

easy leaps; yet might not the length of the leap be increased by practice?

The North American reviewer's position, that the higher brute animals have

comparatively little instinct and no intelligence, is a heavy blow and great

discouragement to dogs, horses, elephants, and monkeys. Thus stripped of

their all, and left to shift for themselves as they may in this hard world,

their pursuit and seeming attainment of knowledge under such peculiar

difficulties are interesting to contemplate. However, we are not so sure as

is the critic that instinct regularly increases downward and decreases

upward in the scale of being. Now that the case of the bee is reduced to

moderate proportions,[III-19] we know of nothing in instinct surpassing that

of an animal so high as a bird, the talegal, the male of which plumes

himself upon making a hot-bed in which to batch his partner's eggs--which

he tends and regulates the beat of about as carefully and skillfully as the

unplumed biped does an eccaleobion.[III-20]

As to the real intelligence of the higher brutes, it has been ably defended

by a far more competent observer, Mr. Agassiz, to whose conclusions we

yield a general assent, although we cannot quite place the best of dogs "in

that respect upon a level with a considerable proportion of poor humanity,"

nor indulge the hope, or indeed the desire, of a renewed acquaintance with

the whole animal kingdom in a future life.

The assertion that acquired habitudes or instincts, and acquired

structures, are not heritable, any breeder or good observer can refute.

That "the human mind has become what it is out of a developed

instinct," is a statement which Mr. Darwin nowhere makes, and, we presume,

would not accept. That he would have us believe that individual animals

acquire their instincts gradually,[III-21] is a statement which must have

been penned in inadvertence both of the very definition of instinct, and of

everything we know of in Mr. Darwin's book.

It has been attempted to destroy the very foundation of Darwin's hypothesis

by denying that there are any wild varieties, to speak of, for natural

selection to operate upon. We cannot gravely sit down to prove that wild

varieties abound. We should think it just as necessary to prove that snow

falls in winter. That variation among plants cannot be largely due to

hybridism, and that their variation in Nature is not essentially different

from much that occurs in domestication, and, in the long-run, probably

hardly less in amount, we could show if our space permitted.

As to the sterility of hybrids, that can no longer be insisted upon as

absolutely true, nor be practically used as a test between species and

varieties, unless we allow that hares and rabbits are of one species. That

such sterility, whether total or partial, subserves a purpose in keeping

species apart, and was so designed, we do not doubt. But the critics fail

to perceive that this sterility proves nothing whatever against the

derivative origin of the actual species; for it may as well have been

intended to keep separate those forms which have reached a certain amount

of divergence, as those which were always thus distinct.

The argument for the permanence of species, drawn from the identity with

those now living of cats, birds, and other animals preserved in Egyptian

catacombs, was good enough as used by Cuvier against St.-Hilaire, that is,

against the supposition that time brings about a gradual alteration of

whole species; but it goes for little against Darwin, unless it be proved

that species never vary, or that the perpetuation of a variety necessitates

the extinction of the parent breed. For Darwin clearly maintains--what the

facts warrant--that the mass of a species remains fixed so long as it

exists at all, though it may set off a variety now and then. The variety may

finally supersede the parent form, or it may coexist with it; yet it does

not in the least hinder the unvaried stock from continuing true to the

breed, unless it crosses with it. The common law of inheritance may be

expected to keep both the original and the variety mainly true as long as

they last, and none the less so because they have given rise to occasional

varieties. The tailless Manx cats, like the curtailed fox in the fable, have

not induced the normal breeds to dispense with their tails, nor have the

Dorkings (apparently known to Pliny) affected the permanence of the common

sort of fowl.

As to the objection that the lower forms of life ought, on Darwin's theory,

to have been long ago improved out of existence, and replaced by higher

forms, the objectors forget what a vacuum that would leave below, and what

a vast field there is to which a simple organization is best adapted, and

where an advance would be no improvement, but the contrary. To accumulate

the greatest amount of being upon a given space, and to provide as much

enjoyment of life as can be under the conditions, is what Nature seems to

aim at; and this is effected by diversification.

Finally, we advise nobody to accept Darwin's or any other derivative theory

as true. The time has not come for that, and perhaps never will. We also

advise against a similar credulity on the other side, in a blind faith that

species--that the manifold sorts and forms of existing animals and

vegetables--"have no secondary cause." The contrary is already not

unlikely, and we suppose will hereafter become more and more probable. But

we are confident that, if a derivative hypothesis ever is established, it

will be so on a solid theistic ground.

Meanwhile an inevitable and legitimate hypothesis is on trial--an

hypothesis thus far not untenable--a trial just now very useful to science,

and, we conclude, not harmful to religion, unless injudicious assailants

temporarily make it so.

One good effect is already manifest; its enabling the advocates of the

hypothesis of a multiplicity of human species to perceive the double

insecurity of their ground. When the races of men are admitted to be of one

species, the corollary, that they are of one origin, may be expected to

follow. Those who allow them to be of one species must admit an actual

diversification into strongly-marked and persistent varieties, and so admit

the basis of fact upon which the Darwinian hypothesis is built; while those,

on the other hand, who recognize several or numerous human species, will

hardly be able to maintain that such species were primordial and

supernatural in the ordinary sense of the word.

The English mind is prone to positivism and kindred forms of materialistic

philosophy, and we must expect the derivative theory to be taken up in that

interest. We have no predilection for that school, but the contrary. If we

had, we might have looked complacently upon a line of criticism which would

indirectly, but effectively, play into the hands of positivists and

materialistic atheists generally. The wiser and stronger ground to take is,

that the derivative hypothesis leaves the argument for design, and

therefore for a designer, as valid as it ever was; that to do any work by an

instrument must require, and therefore presuppose, the exertion rather of

more than of less power than to do it directly; that whoever would be a

consistent theist should believe that Design in the natural world is

coextensive with Providence, and hold as firmly to the one as he does to

the other, in spite of the wholly similar and apparently insuperable

difficulties which the mind encounters whenever it endeavors to develop the

idea into a system, either in the material and organic, or in the moral

world. It is enough, in the way of obviating objections, to show that the

philosophical difficulties of the one are the same, and only the same, as

of the other. IV

SPECIES AS TO VARIATION,

GEOGRAPHICAL

DISTRIBUTION,

AND SUCCESSION

(American Journal of Science and Arts, May, 1863)

Etude sur l'Espece, a l'Occasion d'une Revision de la Famille des

Cupuliferes, par M. ALPHONSE DE CANDOLLE.-- This is the title of a paper by

M. Alph. De Candolle, growing out of his study of the oaks. It was

published in the November number of the Bibliotheque Universelle, and

separately issued as a pamphlet. A less inspiring task could hardly be

assigned to a botanist than the systematic elaboration of the genus Quercus

and its allies. The vast materials assembled under De Candolle's hands,

while disheartening for their bulk, offered small hope of novelty. The

subject was both extremely trite and extremely difficult. Happily it

occurred to De Candolle that an interest might be imparted to an onerous

undertaking, and a work of necessity be turned to good account for science,

by studying the oaks in view of the question of species. What this term

species means, or should mean, in natural history, what the limits of

species, inter se or chronologically, or in geographical distribution, their

modifications, actual or probable, their origin, and their destiny--these

are questions which surge up from time to time; and now and then in the

progress of science they come to assume a new and hopeful interest. Botany

and zoology, geology, and what our author, feeling the want of a new term

proposes to name epiontology, [IV-1] all lead up to and converge into this

class of questions, while recent theories shape and point the discussion So

we look with eager interest to see what light the study of oaks by a very

careful experienced and conservative botanist, particularly conversant with

the geographical relations of plants may throw upon the subject.

The course of investigation in this instance does not differ from that

ordinarily pursued by working botanists nor, in deed are the theoretical

conclusions other than those to which a similar study of other orders might

not have equally led. The oaks afford a very good occasion for the

discussion of questions which press upon our attention, and perhaps they

offer peculiarly good materials on account of the number of fossil species.

Preconceived notions about species being laid aside, the specimens in hand

were distributed, according to their obvious resemblances, into groups of

apparently identical or nearly identical forms, which were severally

examined and compared. Where specimens were few, as from countries little

explored, the work was easy, but the conclusions, as will be seen, of small

value. The fewer the materials, the smaller the likelihood of forms

intermediate between any two, and--what does not appear being treated upon

the old law-maxim as non-existent--species are readily enough defined.

Where, however, specimens abound, as in the case of the oaks of Europe, of

the Orient, and of the United States, of which the specimens amounted to

hundreds, collected at different ages, in varied localities, by botanists

of all sorts of views and predilections--here alone were data fit to draw

useful conclusions from. Here, as De Candolle remarks, he had every

advantage, being furnished with materials more complete than any one person

could have procured from his own herborizations, more varied than if he had

observed a hundred times over the same forms in the same district, and more

impartial than if they had all been amassed by one person with his own

ideas or predispositions. So that vast herbaria, into which contributions

from every source have flowed for years, furnish the best possible data--at

least are far better than any practicable amount of personal

herborization--or the comparative study of related forms occurring over

wide tracts of territory. But as the materials increase, so do the

difficulties. Forms, which appeared totally distinct, approach or blend

through intermediate gradations; characters, stable in a limited number of

instances or in a limited district, prove unstable occasionally, or when

observed over a wider area; and the practical question is forced upon the

investigator, What here is probably fixed and specific, and what is

variant, pertaining to individual, variety, or race?

In the examination of these rich materials, certain characters were found

to vary upon the same branch, or upon the same tree, sometimes according to

age or development, sometimes irrespective of such relations or of any

assignable reasons. Such characters, of course, are not specific, although

many of them are such as would have been expected to be constant in the

same species, and are such as generally enter into specific definitions.

Variations of this sort, De Candolle, with his usual painstaking, classifies

and tabulates, and even expresses numerically their frequency in certain

species. The results are brought well to view in a systematic enumeration:

1. Of characters which frequently vary upon the same branch: over a dozen

such are mentioned.

2. Of those which sometimes vary upon the same branch: a smaller number of

these are mentioned.

3. Those so rare that they might be called monstrosities.

Then he enumerates characters, ten in number, which he has never found to

vary on the same branch, and which, therefore, may better claim to be

employed as specific. But, as among them he includes the duration of the

leaves, the size of the cupule, and the form and size of its scales, which

are by no means quite uniform in different trees of the same species, even

these characters must be taken with allowance. In fact, having first

brought together, as groups of the lowest order, those forms which varied

upon the same stock, he next had to combine similarly various forms which,

though not found associated upon the same branch, were thoroughly blended

by intermediate degrees:

"The lower groups (varieties or races) being thus constituted, I have given

the rank of species to the groups next above these, which differ in other

respects, i.e., either in characters which were not found united upon

certain individuals, or in those which do not show transitions from one

individual to another. For the oaks of regions sufficiently known, the

species thus formed rest upon satisfactory bases, of which the proof can be

furnished. It is quite otherwise with those which are represented in our

herbaria by single or few specimens. These are provisional species--species

which may hereafter fall to the rank of simple varieties. I have not been

inclined to prejudge such questions; indeed, in this regard, I am not

disposed to follow those authors whose tendency is, as they say, to reunite

species. I never reunite them without proof in each particular case; while

the botanists to whom I refer do so on the ground of analogous variations

or transitions occurring in the same genus or in the same family. For

example resting on the fact that Quercus hex, Q. coccifera, Q. acutifolia,

etc., have the leaves sometimes entire and sometimes toothed upon the same

branch, or present transitions from one tree to another, I might readily

have united my Q. Tlapuxahuensis to Q. Sartorii of Liebmann, since these

two differ only in their entire or their toothed leaves. From the fact that

the length of the peduncle varies in Q. Robur and many other oaks, I might

have combined Q. Seemannii Liebm. with Q. salicifolia Nee. I have not

admitted these inductions, but have demanded visible proof in each

particular case. Many species are thus left as provisional; but, in

proceeding thus, the progress of the science will be more regular, and the

synonymy less dependent upon the caprice or the theoretical opinions of

each author."

This is safe and to a certain degree judicious, no doubt, as respects

published species. Once admitted, they may stand until they are put down by

evidence, direct or circumstantial. Doubtless a species may rightfully be

condemned on good circumstantial evidence. But what course does De Candolle

pursue in the case--of every-day occurrence to most working botanists,

having to elaborate collections from countries not so well explored as

Europe--when the forms in question, or one of the two, are as yet unnamed?

Does he introduce as a new species every form which he cannot connect by

ocular proof with a near relative, from which it differs only in

particulars which he sees are inconstant in better known species of the

same group? We suppose not. But, if he does, little improvement for the

future upon the state of things revealed in the following quotation can be

expected:

"In the actual state of our knowledge, after having seen nearly all the

original specimens, and in some species as many as two hundred

representatives from different localities, I estimate that, out of the

three hundred species of Cupuliferae which will be enumerated in the

Prodromus, two-thirds at least are provisional species. In general, when we

consider what a multitude of species were described from a single specimen,

or from the forms of a single locality, of a single country, or are badly

described, it is difficult to believe that above one-third of the actual

species in botanical works will remain unchanged."

Such being the results of the want of adequate knowledge, how is it likely

to be when our knowledge is largely increased? The judgment of so practised

a botanist as De Candolle is important in this regard, and it accords with

that of other botanists of equal experience.

"They are mistaken," he pointedly asserts, "who repeat that the greater

part of our species are clearly limited, and that the doubtful species are

in a feeble minority. This seemed to be true, so long as a genus was

imperfectly known, and its species were founded upon few specimens, that is

to say, were provisional. Just as we come to know them better, intermediate

forms flow in, and doubts as to specific limits augment."

De Candolle insists, indeed, in this connection, that the higher the rank

of the groups the more definite their limitation, or, in other terms, the

fewer the ambiguous or doubtful forms, that genera are more strictly

limited than species tribes than genera, orders than tribes, etc. We are

not convinced of this Often where it has appeared to be so, advancing

discovery has brought intermediate forms to light, perplexing to the

systematist. "They are mistaken, we think more than one systematic botanist

will say, "who repeat that the greater part of our natural orders and

tribes are absolutely limited," however we may agree that we will limit

them. Provisional genera we suppose are proportionally hardly less common

than provisional species; and hundreds of genera are kept up on

considerations of general propriety or general convenience, although well

known to shade off into adjacent ones by complete gradations. Somewhat of

this greater fixity of higher groups, therefore, is rather apparent than

real. On the other hand, that varieties should be less definite than

species, follows from the very terms employed. They are ranked as

varieties, rather than species, just because of their less definiteness.

Singular as it may appear, we have heard it denied that spontaneous

varieties occur. De Candolle makes the important announcement that, in the

oak genus, the best known species are just those which present the greatest

number of spontaneous varieties and sub-varieties. The maximum is found in

Q. Robur, with twenty-eight varieties, all spontaneous. Of Q. Lusitanica

eleven varieties are enumerated, of Q. Calliprinos ten, of Q. coccifera

eight, * etc. And he significantly adds that "these very species which offer

such numerous modifications are themselves ordinarily surrounded by other

forms, provisionally called species, because of the absence of known

transitions or variations, but to which some of these will probably have to

be joined hereafter." The inference is natural, if not inevitable, that the

difference between such species and such varieties is only one of degree,

either as to amount of divergence, or of hereditary fixity, or as to the

frequency or rarity at the present time of intermediate forms.

This brings us to the second section of De Candolle's article, in which he

passes on, from the observation of the present forms and affinities of

cupuliferous plants, to the consideration of their probable history and

origin. Suffice it to say, that he frankly accepts the inferences derived

from the whole course of observation, and contemplates a probable

historical connection between congeneric species. He accepts and, by

various considerations drawn from the geographical distribution of European

Cupuliferae, fortifies the conclusion--long ago arrived at by Edward

Forbes--that the present species, and even some of their varieties, date

back to about the close of the Tertiary epoch, since which time they have

been subject to frequent and great changes of habitation or limitation, but

without appreciable change of specific form or character; that is, without

profounder changes than those within which a species at the present time is

known to vary. Moreover, he is careful to state that he is far from

concluding that the time of the appearance of a species in Europe at all

indicates the time of its origin. Looking back still further into the

Tertiary epoch, of which the vegetable remains indicate many analogous, but

few, if any, identical forms, he concludes, with Heer and others, that

specific changes of form, as well as changes of station, are to be

presumed; and, finally, that "the theory of a succession of forms through

the deviation of anterior forms is the most natural hypothesis, and the

most accordant with the known facts in palaeontology, geographical botany

and zoology, of anatomical structure and classification: but direct proof

of it is wanting, and moreover, if true, it must have taken place very

slowly; so slowly, indeed, that its effects are discernible only after a

lapse of time far longer than our historic epoch."

In contemplating the present state of the species of Cupuliferae in Europe,

De Candolle comes to the conclusion that, while the beech is increasing,

and extending its limits southward and westward (at the expense of

Coniferae and birches), the common oak, to some extent, and the Turkey oak

decidedly, are diminishing and retreating, and this wholly irrespective of

man's agency. This is inferred of the Turkey oak from the great gaps found

in its present geographical area, which are otherwise inexplicable, and

which he regards as plain indications of a partial extinction. Community of

descent of all the individuals of species is of course implied in these and

all similar reasonings.

An obvious result of such partial extinction is clearly enough brought to

view The European oaks (like the American species) greatly tend to vary

that is they manifest an active disposition to produce new forms Every form

tends to become hereditary and so to pass from the state of mere variation

to that of race and of these competing incipient races some only will

survive. Quercus Robur offers a familiar illustration of the manner in

which one form may in the course of time become separated into two or more

distinct ones.

To Linnaeus this common oak of Europe was all of one species. But of late

years the greater number of European botanists have regarded it as

including three species, Q. pedunculata, Q. sessiliflora, and Q. pubescens.

De Candolle looks with satisfaction to the independent conclusion which he

reached from a long and patient study of the forms (and which Webb, Gay,

Bentham, and others, had equally reached), that the view of Linnaeus was

correct, inasmuch as it goes to show that the idea and the practical

application of the term species have remained unchanged during the century

which has elapsed since the publication of the "Species Plantarum." But,

the idea remaining unchanged, the facts might appear under a different

aspect, and the conclusion be different, under a slight and very supposable

change of circumstances. Of the twenty-eight spontaneous varieties of Q.

Robur, which De Candolle recognizes, all but six, he remarks, fall

naturally under the three sub-species, pedunculata, sessiliflora, and

pubescens, and are therefore forms grouped around these as centres; and,

moreover, the few connecting forms are by no means the most common. Were

these to die out, it is clear that the three forms which have already been

so frequently taken for species would be what the group of four or five

provisionally admitted species which closely surround Q. Robur now are. The

best example of such a case, as having in all probability occurred through

geographical segregation and partial extinction, is that of the cedar, thus

separated into the Deodar, the Lebanon, and the Atlantic cedars--a case

admirably worked out by Dr. Hooker two or three years ago. [IV-2]

A special advantage of the Cupuliferae for determining the probable

antiquity of existing species in Europe, De Candolle finds in the size and

character of their fruits. However it may be with other plants (and he

comes to the conclusion generally that marine currents and all other means

of distant transport have played only a very small part in the actual

dispersion of species), the transport of acorns and chestnuts by natural

causes across an arm of the sea in a condition to germinate, and much more

the spontaneous establishment of a forest of oaks or chestnuts in this way,

De Candolle conceives to be fairly impossible in itself, and contrary to

all experience. From such considerations, i.e., from the actual dispersion

of the existing species (with occasional aid from post-tertiary deposits),

it is thought to be shown that the principal Cupuliferae of the Old World

attained their actual extension before the present separation of Sicily,

Sardinia and Corsica, and of Britain, from the European Continent.

This view once adopted, and this course once entered upon, has to be

pursued farther. Quercus Robur of Europe with its bevy of admitted

derivatives, and its attending species only provisionally admitted to that

rank, is very closely related to certain species of Eastern Asia, and of

Oregon and California--so closely that "a view of the specimens by no means

forbids the idea that they have all originated from Q. Robur, or have

originated, with the latter, from one or more preceding forms so like the

present ones that a naturalist could hardly know whether to call them

species or varieties." Moreover, there are fossil leaves from diluvian

deposits in Italy, figured by Gaudin, which are hardly distinguishable from

those of Q. Robur on the one hand, and from those of Q. Douglasii, etc., of

California, on the other. No such leaves are found in any tertiary deposit

in Europe; but such are found of that age, it appears, in Northwest

America, where their remote descendants still flourish. So that the probable

genealogy of Q. Robur, traceable in Europe up to the commencement of the

present epoch, looks eastward and far into the past on far-distant shores.

Quercus Ilex, the evergreen oak of Southern Europe and Northern Africa,

reveals a similar archaeology; but its presence in Algeria leads De

Candolle to regard it as a much more ancient denizen of Europe than Q.

Robur; and a Tertiary oak, Q. ilicoides, from a very old Miocene bed in

Switzerland, is thought to be one of its ancestral forms. This high

antiquity once established, it follows almost of course that the very

nearly-related species in Central Asia, in Japan, in California, and even

our own live-oak with its Mexican relatives, may probably enough be

regarded as early offshoots from the same stock with Q. hex.

In brief--not to continue these abstracts and remarks, and without

reference to Darwin's particular theory (which De Candolle at the close

very fairly considers)--if existing species, or many of them, are as

ancient as they are now generally thought to be, and were subject to the

physical and geographical changes (among them the coming and the going of

the glacial epoch) which this antiquity implies; if in former times they

were as liable to variation as they now are; and if the individuals of the

same species may claim a common local origin, then we cannot wonder that

"the theory of a succession of forms by deviations of anterior forms"

should be regarded as "the most natural hypothesis," nor at the general

advance made toward its acceptance.

The question being, not, how plants and animals originated, but, how came

the existing animals and plants to be just where they are and what they

are, it is plain that naturalists interested in such inquiries are mostly

looking for the answer in one direction. The general drift of opinion, or

at least of expectation, is exemplified by this essay of De Candolle; and

the set and force of the current are seen by noticing how it carries along

naturalists of widely different views and prepossessions--some faster and

farther than others--but all in one way. The tendency is, we may say, to

extend the law of continuity, or something analogous to it, from inorganic

to organic Nature, and in the latter to connect the present with the past

in some sort of material connection. The generalization may indeed be

expressed so as not to assert that the connection is genetic, as in Mr.

Wallace's formula: "Every species has come into existence coincident both

in time and space with preexisting closely-allied species." Edward Forbes,

who may be called the originator of this whole line of inquiry, long ago

expressed a similar view. But the only material sequence we know, or can

clearly conceive, in plants and animals, is that from parent to progeny;

and, as De Candolle implies, the origin of species and that of races can

hardly be much unlike, nor governed by other than the same laws, whatever

these may be.

The progress of opinion upon this subject in one generation is not badly

represented by that of De Candolle himself, who is by no means prone to

adopt new views without much consideration. In an elementary treatise

published in the year 1835, he adopted and, if we rightly remember,

vigorously maintained, Schouw's idea of the double or multiple origin of

species, at least of some species--a view which has been carried out to its

ultimate development only perhaps by Agassiz, in the denial of any necessary

genetic connection among the individuals of the same species, or of any

original localization more restricted than the area now occupied by the

species. But in i855, in his "Geographic Botanique," the multiple

hypothesis, although in principle not abandoned, loses its point, in view

of the probable high antiquity of existing species. The actual vegetation

of the world being now regarded as a continuation, through numerous

geological, geographical, and more recently historical changes, of anterior

vegetations, the actual distribution of plants is seen to be a consequence

of preceding conditions; and geological considerations, and these alone,

may be expected to explain all the facts--many of them so curious and

extraordinary--of the actual geographical distribution of the species. In

the present essay, not only the distribution but the origin of congeneric

species is regarded as something derivative; whether derived by slow and

very gradual changes in the course of ages, according to Darwin, or by a

sudden, inexplicable change of their tertiary ancestors, as conceived by

Heer, De Candolle hazards no opinion. It may, however, be inferred that he

looks upon "natural selection" as a real, but insufficient cause; while

some curious remarks upon the number of monstrosities annually produced,

and the possibility of their enduring, may be regarded as favorable to

Heer's view.

As an index to the progress of opinion in the direction referred to, it

will be interesting to compare Sir Charles Lyell's well-known chapters of

twenty or thirty years ago, in which the permanence of species was ably

maintained, with his treatment of the same subject in a work just issued in

England, which, however, has not yet reached us.

A belief of the derivation of species may be maintained along with a

conviction of great persistence of specific characters. This is the idea of

the excellent Swiss vegetable palaeontologist, Heer, who imagines a sudden

change of specific type at certain periods, and perhaps is that of Pictet.

Falconer adheres to somewhat similar views in his elaborate paper on

elephants, living and fossil, in the Natural History Review for January

last. Noting that "there is clear evidence of the true mammoth having

existed in America long after the period of the northern drift, when the

surface of the country had settled down into its present form, and also in

Europe so late as to have been a contemporary of the Irish elk, and on the

other hand that it existed in England so far back as before the deposition

of the bowlder clay; also that four well-defined species of fossil elephant

are known to have existed in Europe; that "a vast number of the remains of

three of these species have been exhumed over a large area in Europe; and,

even in the geological sense, an enormous interval of time has elapsed

between the formation of the most ancient and the most recent of these

deposits, quite sufficient to test the persistence of specific characters

in an elephant," he presents the question, "Do, then, the successive

elephants occurring in these strata show any signs of a passage from the

older form into the newer?"

To which the reply is: "If there is one fact which is impressed on the

conviction of the observer with more force than any other, it is the

persistence and uniformity of the characters of the molar teeth in the

earliest known mammoth and his most modern successor . . . Assuming the

observation to be correct, what strong proof does it not afford of the

persistence and constancy, throughout vast intervals of time, of the

distinctive characters of those organs which arc most concerned in the

existence and habits of the species? If we cast a glance back on the long

vista of physical changes which our planet has undergone since the Neozoic

epoch, we can nowhere detect signs of a revolution more sudden and

pronounced, or more important in its results, than the intercalation and

sudden disappearance of the glacial period. Yet the 'dicyclotherian'

mammoth lived before it, and passed through the ordeal of all the hard

extremities it involved, bearing his organs of locomotion and digestion all

but unchanged. Taking the group of four European fossil species above

enumerated, do they show any signs in the successive deposits of a

transition from the one form into the other? Here again the result of my

observation, in so far as it has extended over the European area, is, that

the specific characters of the molars are constant in each, within a

moderate range of variation, and that we nowhere meet with intermediate

forms." . . .

Dr. Falconer continues (page 80):

"The inferences which I draw from these facts are not opposed to one of the

leading propositions of Darwin's theory. With him, I have no faith in the

opinion that the mammoth and other extinct elephants made their appearance

suddenly, after the type in which their fossil remains are presented to us.

The most rational view seems to be, that they are in some shape the

modified descendants of earlier progenitors. But if the asserted facts be

correct, they seem clearly to indicate that the older elephants of Europe,

such as E. meridionalis and E. antiguus, were not the stocks from which the

later species, E. primigenius and E. Africanus sprung, and that we must

look elsewhere for their origin. The nearest affinity, and that a very

close one, of the European E. meridionalis is with the Miocene E.

planifrons of India; and of E. primigenius, with the existing India

species.

"Another reflection is equally strong in my mind--that the means which have

been adduced to explain the origin of the species by 'natural selection,'

or a process of variation from external influences, are inadequate to

account for the phenomena. The law of phyllotaxis, which governs the

evolution of leaves around the axis of a plant, is as nearly constant in

its manifestation as any of the physical laws connected with the material

world. Each instance, however different from another, can be shown to be a

term of some series of continued fractions. When this is coupled with the

geometrical law governing the evolution of form, so manifest in some

departments of the animal kingdom, e. g., the spiral shells of the

Mollusca, it is difficult to believe that there is not, in Nature, a

deeper-seated and innate principle, to the operation of which natural

selection is merely an adjunct. The whole range of the Mammalia, fossil and

recent, cannot furnish a species which has had a wider geographical

distribution, and passed through a longer term of time, and through more

extreme changes of climatal conditions, than the mammoth. If species are so

unstable, and so susceptible of mutation through such influences, why does

that extinct form stand out so signally a monument of stability? By his

admirable researches and earnest writings, Darwin has, beyond all his

contemporaries, given an impulse to the philosophical investigation of the

most backward and obscure branch of the biological sciences of his day; he

has laid the foundations of a great edifice; but he need not be surprised

if, in the progress of erection, the superstructure is altered by his

successors, like the Duomo of Milan from the Roman to a different style of

architecture."

Entertaining ourselves the opinion that something more than natural

selection is requisite to account for the orderly production and succession

of species, we offer two incidental remarks upon the above extract.

1. We find in it--in the phrase "natural selection, or a process of

variation from external influences"--an example of the very common

confusion of two distinct things, viz., variation and natural selection.

The former has never yet been shown to have its cause in "external

influences," nor to occur at random. As we have elsewhere insisted, if not

inexplicable, it has never been explained; all we can yet say is, that

plants and animals are prone to vary, and that some conditions favor

variation. Perhaps in this Dr. Falconer may yet find what he seeks: for "it

is difficult to believe that there is not in nature a deeper-seated and

innate principle, to the operation of which natural selection is merely an

adjunct." The latter, which is the ensemble of the external influences,

including the competition of the individuals them selves, picks out certain

variations as they arise, but in no proper sense can be said to originate

them

2. Although we are not quite sure how Dr Falconer in tends to apply the law

of phyllotaxis to illustrate his idea, we fancy that a pertinent

illustration may be drawn from it in this way. There are two species of

phyllotaxis, perfectly distinct, and we suppose, not mathematically

reducible the one to the other, viz.: (1.) That of alternate leaves, with

its vane ties and (2.) That of verticillate leaves, of which opposite leaves

present the simplest case That although generally constant a change from one

variety of alternate phyllotaxis to an other should occur on the same axis,

or on successive axes, is not surprising, the different sorts being terms

of a regular series--although indeed we have not the least idea as to how

the change from the one to the other comes to pass But it is interesting

and in this connection perhaps instructive, to remark that while some

dicotyledonous plants hold to the verticillate, i.e., opposite-leaved

phyllotaxis throughout, a larger number--through the operation of some deep

seated and innate principle which we cannot fathom--change abruptly into

the other species at the second or third node, and change back again in the

flower, or else effect a synthesis of the two species in a manner which is

puzzling to understand. Here is a change from one fixed law to another, as

unaccountable, if not as great, as from one specific form to another.

An elaborate paper on the vegetation of the Tertiary period in the

southeast of France, by Count Gaston de Saporta, published in the Annales

des Sciences Naturelles in 1862, vol. xvi., pp. 309-344--which we have not

space to analyze--is worthy of attention from the general inquirer, on

account of its analysis of the Tertiary flora into its separate types,

Cretaceous, Austral, Tropical, and Boreal, each of which has its separate

and different history--and for the announcement that "the hiatus, which, in

the idea of most geologists, intervened between the close of the Cretaceous

and the beginning of the Tertiary, appears to have had no existence, so far

as concerns the vegetation; that in general it was not by means of a total

overthrow, followed by a complete new emission of species, that the flora

has been renewed at each successive period; and that while the plants of

Southern Europe inherited from the Cretaceous period more or less rapidly

disappeared, as also the austral forms, and later the tropical types (except

the laurel, the myrtle, and the Chamaerops humilis), the boreal types,

coming later, survived all the others, and now compose, either in Europe,

or in the north of Asia, or in North America, the basis of the actual

arborescent vegetation. Especially "a very considerable number of forms

nearly identical with tertiary forms now exist in America, where they have

found, more easily than in our soil--less vast and less extended

southward--refuge from ulterior revolutions," The extinction of species is

attributed to two kinds of causes; the one material or physical, whether

slow or rapid; the other inherent in the nature of organic beings,

incessant, but slow, in a manner latent, but somehow assigning to the

species, as to the individuals, a limited period of existence, and, in some

equally mysterious but wholly natural way, connected with the development

of organic types: "By type meaning a collection of vegetable forms

constructed upon the same plan of organization, of which they reproduce the

essential lineaments with certain secondary modifications, and which appear

to run back to a common point of departure."

In this community of types, no less than in the community of certain

existing species, Saporta recognizes a prolonged material union between

North America and Europe in former times. Most naturalists and geologists

reason in the same way--some more cautiously than others--yet perhaps most

of them seem not to perceive how far such inferences imply the doctrine of

the common origin of related species.

For obvious reasons such doctrines are likely to find more favor with

botanists than with zoologists. But with both the advance in this direction

is seen to have been rapid and great; yet to us not unexpected. We note,

also, an evident disposition, notwithstanding some endeavors to the

contrary, to allow derivative hypotheses to stand or fall upon their own

merits--to have indeed upon philosophical grounds certain presumptions in

their favor--and to be, perhaps, quite as capable of being turned to good

account as to bad account in natural theology.[IV-3]

Among the leading naturalists, indeed, such views--taken in the widest

sense--have one and, so far as we are now aware, only one thoroughgoing and

thoroughly consistent opponent, viz., Mr. Agassiz.

Most naturalists take into their very conception of a species, explicitly

or by implication, the notion of a material connection resulting from the

descent of the individuals composing it from a common stock, of local

origin. Agassiz wholly eliminates community of descent from his idea of

species, and even conceives a species to have been as numerous in

individuals and as wide-spread over space, or as segregated in

discontinuous spaces, from the first as at the later period.

The station which it inhabits, therefore, is with other naturalists in no

wise essential to the species, and may not have been the region of its

origin. In Agassiz's view the habitat is supposed to mark the origin, and

to be a part of the character of the species. The habitat is not merely the

place where it is, but a part of what it is.

Most naturalists recognize varieties of species; and many, like De

Candolle, have come to conclude that varieties of the highest grade, or

races, so far partake of the characteristics of species, and are so far

governed by the same laws, that it is often very difficult to draw a clear

and certain distinction between the two. Agassiz will not allow that

varieties or races exist in Nature, apart from man's agency.

Most naturalists believe that the origin of species is supernatural, their

dispersion or particular geographical area, natural, and their extinction,

when they disappear, also the result of physical causes. In the view of

Agassiz, if rightly understood, all three are equally independent of

physical cause and effect, are equally supernatural.

In comparing preceding periods with the present and with each other, most

naturalists and palaeontologists now appear to recognize a certain number of

species as having survived from one epoch to the next, or even through more

than one formation, especially from the Tertiary into the post-Tertiary

period, and from that to the present age. Agassiz is understood to believe

in total extinctions and total new creations at each successive epoch, and

even to recognize no existing species as ever contemporary with extinct

ones, except in the case of recent exterminations.

These peculiar views if sustained will effectually dispose of every form of

derivative hypothesis.

Returning for a moment to De Candolle's article, we are disposed to notice

his criticism of Linnaeus's "definition" of the term species (Philosophia

Botanica, No. 157): "Species tot numeramus quot diversae formae in

principio sunt creatae"-- which he declares illogical, inapplicable, and

the worst that has been propounded. "So, to determine if a form is

specific, it is necessary to go back to its origin which is impossible A

definition by a character which can never be verified is no definition at

all."

Now as Linnaeus practically applied the idea of species with a sagacity

which has never been surpassed and rarely equaled and indeed may be said to

have fixed its received meaning in natural history, it may well be inferred

that in the phrase above cited he did not so much undertake to frame a

logical definition, as to set forth the idea which, in his opinion, lay at

the foundation of species; on which basis A.L. Jussieu did construct a

logical definition--"Nunc rectius definitur perennis individuorum similium

successio continuata generatione renascentium." The fundamental idea of

species, we would still maintain, is that of a chain of which

genetically-connected individuals are the links. That, in the practical

recognition of species, the essential characteristic has to be inferred, is

no great objection--the general fact that like engenders like being an

induction from a vast number of instances, and the only assumption being

that of the uniformity of Nature. The idea of gravitation, that of the

atomic constitution of matter, and the like, equally have to be verified

inferentially. If we still hold to the idea of Linnaeus, and of Agassiz,

that existing species were created independently and essentially all at

once at the beginning of the present era, we could not better the

propositions of Linnaeus and of Jussieu. If; on the other hand, the time has

come in which we may accept, with De Candolle, their successive

origination, at the commencement of the present era or before, and even by

derivation from other forms, then the "in principio" of Linnaeus will refer

to that time, whenever it was, and his proposition be as sound and wise as

ever.

In his "Geographie Botanique" (ii., 1068-1077) De Candolle discusses this

subject at length, and in the same interest. Remarking that of the two

great facts of species, viz., likeness among the individuals, and

genealogical connection, zoologists have generally preferred the

latter,[IV-4] while botanists have been divided in opinion, he pronounces

for the former as the essential thing, in the following argumentative

statement: