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over less fortunate communities. Hence, it would follow that those males and females which are endowed with the capability of propagating multitudinous neuters, would multiply more rapidly than others, and the peculiar variation would go on till the relative numbers of neutral and sexual offspring would be adjusted to the wants of the communities respectively.

As regards this solution of the difficulty in question, it is sufficient to say that the supposed changes are not known ever to have occurred in the past, or to be going on in the present. Moreover, it assumes so many things which, if true, would be quite as hard to explain as the original difficulty, that we are compelled to believe that the problem still waits for a solution.

Another difficulty grows out of the observed geographical distribution of plants and animals. Regions which are separated by wide oceans, lofty and continuous mountain barriers, or by the interlocation of a tropical climate, present but few closely allied forms in common. This is not inconsistent with Darwin's theory, as the ancestral types of living forms are supposed to have originated far back in time, when the relations between land and water, mountain and plain, heat and cold, were very different from what they are at present. The diverging descendants of the primitive types, being separated by the upheaval of mountains and the subsidence of land, giving rise to oceans, would go on diverging, under different conditions of existence, becoming more and more unlike. The general facts of geographical distribution, as already suggested, agree with this hypothesis. But there are some identical, and many closely allied species found on opposite sides of wide oceans and lofty mountain ranges, and in northern and southern hemispheres, with an incompatible tropical climate between them.

If the general diversity of forms, in widely distant regions, is accounted for by long separation, what shall we do with the particular cases of similarity and identity? Darwin replies by suggesting possible modes of migration between divided regions. He supposes the communication between the northern and southern hemispheres to have been effected by two

alternating glacial periods on the two sides of the equator. The author's suggestions under this head can hardly take a higher rank than that of plausible guesses, and therefore can not be accepted as a solution of the difficulty in question. Yet they are deeply interesting and instructive, apart from their bearing on his theory.

Again, if existing living forms have descended, or, rather, ascended, from a few, simple, primitive types, by a slow and scarcely perceptible progress of variation, the geological strata ought to have preserved the remains, not of distinct species, but of a continuous series of forms, running into each other by imperceptible gradations, so that any two forms separated by distinct specific differences, should have, lying between them, other intermediate forms, insensibly graduating into the two species and into each other. Now, Darwin freely admits that the geological record, as far as it has been consulted, testifies to the succession of distinct species, in the absence of intermediate forms. He endeavors to break the force of this objection by first showing the general agreement of the geological record with his theory, and then attempting to account for the particular disagreement by proving that the geological record is too imperfect to be relied upon to sustain the objection.

The general agreement of the facts of geology with Darwin's theory may be thus stated: First, the fossil remains of extinct races show a general progress, in the order of time, from the lower to the higher organic forms. Then, if we take three successive geological formations, naming them A, B and C, from below upward, we shall find that the fossil remains of A are more closely allied to those of B than to those of C, and that those of B are intermediate in form between those of A and C. This holds true, though there may be no identical species connecting the three formations. But the knotty fact for Darwin's theory is, that the transitions are made by leaps from one species to another, and not by an imperceptible gliding of forms into each other, as the theory requires. Darwin seems to be aware that his efforts to adduce a few intermediate

forms are not quite successful, and he falls back, in the end, on the imperfection of the geological record.

Once more, geology not infrequently reveals the sudden appearance and wide-spread prevalence of a new species in formations, in which they had not before existed. This fact, unless its force can be broken by other facts or by cogent arguments, stands in glaring violation, I had almost said contempt of Darwin's theory. The author meets this fact with supposed or imaginary migrations; and in the absence of any clue to the regions from which the new species may have migrated, he again falls back on the imperfections of the geological record.

In conclusion, under this head, what shall we say to the question how far Darwin has succeeded in establishing his theory on a basis of probability?

For myself, I would say, the general drift of the facts and analogies adduced by him is such as to lend a certain plausibility to the theory, while, on the other hand, it seems to me to fail in the encounter with almost all the trial tests of its validity. I think it is confronted, at the present stage of scientific knowledge, by more than one experimentum crucis, before which it will have to wait long before it can assert its claim to general acceptance. To bring the theory to the standard of the inductive logic, it may be said that the steps of induction and deduction have been duly taken, and appropriately elaborated; but attempts at verification have been almost uniformly failures.

Darwin, himself, seems to be conscious of his doubtful success in meeting and removing the objections to his theory. He says: “Indeed it will be thought that I have an overweening confidence in the principle of natural selection, when I do not admit that such wonderful and well-established facts at once annihilate the theory." Again, with regard to the case of neuter insects, he says: "I must confess that, with all my faith in natural selection, I should never have anticipated that this could have been efficient to so high a degree, had not the case of neuter insects convinced me of the fact." One can hardly

forbear a smile at the simplicity of this remark, which reveals at once the spirit of candor and the extreme bias of the author. The facts, which convince him of the wonderful efficiency of the principle of natural selection, will stand, to the majority of thinking minds, as irrefragable objections to his theory, unless more satisfactory explanations of them can be given than any to be found in his book.

DARWINISM IN ITS RELATIONS TO THE

CIES OF THE DAY.

MATERIALISTIC TENDEN

Though we may decide that the theory of natural selection is not sustained by the facts and arguments adduced in its support, not such will be the decision of a large number of the most active minds of our age. Those who approach the question exclusively on the side of material facts and laws, will be almost sure to agree with Darwin; while those who encounter the theory mainly in those deductions which seemingly conflict with long-cherished beliefs, will, as certainly, disagree with him.

But a question of deeper interest is this: What is to be the effect of Darwin's theory on the thought of the present and succeeding generations? I can not resist the conviction that its influence is destined to be profound, far-reaching and controlling. It apparently harmonizes so many facts, and plausibly accounts for so many observed relations; it so falls in with a phase of speculation which is older than Aristotle, and has not been without partisans from that time to this; it apparently bridges so many sloughs of despond and levels so many hills of difficulty for many minds which have long been aching to find their way from inorganic matter, through mere molecular forces, up to the highest manifestations of life, that it can not fail to draw to its investigation and support an important share of the mental activity which is at work at the solution of the great problems of existence.

This brings up the question of the precise relation of Darwin's system to the skeptical philosophy of the day.

This philosophy holds, and is ransacking every corner of the earth, every nook of the ocean-depths, and the records of the ages, stored up in the geological strata, to prove that all organized beings have sprung out of unorganized matter through the action of the mere material forces with which it is endowed. This is not Darwin's doctrine. He expresses the opinion that "life, with its several powers, was originally breathed by the Creator into a few forms, or into one, and that from so simple a beginning, endless forms, most beautiful and most wonderful, have been and are being evolved." The material philosophy would substitute a supposed life-producing agency of the molecular forces of matter for the original inbreathing of life by the Creator, spoken of by our author. Having accomplished this long leap at the outset, the materialist is content make the remainder of the journey with Darwin. This is the relation of Darwinism to modern materialism.

To present a complete view of the subject in hand, it is important to inquire how the materialist proposes to pass over the gulf of gulfs which divides non-living from living matter, -utter passivity and blank insensibility from active, conscious life.

In the first place, there is a certain chemical compound, believed to be an essential constituent of all living beings, and which is not known ever to have been produced outside of living organs. This compound is called protein, and is composed of carbon, oxygen, hydrogen and nitrogen. With the addition of very small proportions of sulphur and phosphorus, it constitutes the principal basis of the living tissues in animals, and is an omnipresent vital product in plants. Of its importance to life, Mulder, one of the highest authorities in organic chemistry, thus speaks: "It is unquestionably the most important of all known substances in the organic kingdom. Without it, no life appears possible on our planet. Through its means the chief phenomena of life are produced."

This substance is supposed to be formed in the vital organs, by the action of carbonic acid, water and ammonia on each other. The problem is, how to compound this important sub

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