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would effect mutations somewhat more decided, but of the same character ? " *

Unquestionably not, replies Mr. Darwin:

sand generations would produce a marked effect, and adapt the form of the fox or dog to the catching of hares instead of rabbits, than that greyhounds can be improved by selection and careful breeding." t

duced perfect as we now see them; but this assumption seems to me to be no explanation, for it leaves the case of the co-adaptations of organic beings to each other and to their physical conditions of life untouched and unexplained."-P. 3. "To give an imaginary example from changes The last cited ingenious writer came to in progress on an island: let the organization the task of attempting to unravel the "mys- bits, but sometimes on hares, become slightly of a canine animal which preyed chiefly on rabtery of mysteries," when a grand series of plastic; let these same changes cause the num embryological researches had brought to ber of rabbits very slowly to decrease, and the light the extreme phases of form that the number of hares to increase; the effect of this higher animals passed through in the course would be that the fox or dog would be driven to of foetal development, and the striking anal- try to catch more hares; his organization, howogies which transitory embryonal phases of ever, being slightly plastic, those individuals a higher species presented to series of lower with the lightest forms, longest limbs, and best species in their permanent or completely de- eyesight, let the difference be ever so small, veloped state. He also instances the abrupt live longer, and to survive during that time of would be slightly favored, and would tend to departure from the specific type manifested the year when food was scarcest; they would by a malformed or monstrous offspring, and also rear more young, which would tend to incalled to mind the cases in which such mal- herit those slight peculiarities. The less fleet formations had lived and propagated the de- ones would be rigidly destroyed. I can see no viating structure. The author of "Ves-more reason to doubt that these causes in a thoutiges," therefore, speculates-and we think not more rashly or unlawfully than his critic has done on other possibilities, other conditions of change, than the Lamarckian ones; as, for example, on the influence of premature birth and of prolonged fœtation in es- Of course, prosaic minds are apt to bore tablishing the beginning of a specific form one by asking for our proofs, and one feels different from that of the parent. And does almost provoked, when seduced to the brink not the known history of certain varieties, of such a draught of forbidden knowledge such as that of M. Graux's cachemir-wooled as the transmutationists offer, to have the sheep, which began suddenly by malforma- Circean cup dashed away by the dry remark tion, show the feasibility of this view? of a president of the British Association:"The whole train of animated beings," "Observation of animals in a state of nature writes the author of "Vestiges of Creation," is required to show their degree of plasticity, or "are the results first, of an inherent impulse the extent to which varieties do arise: whereby in the forms of life to advance, in definite grounds may be had for judging of the proba times, through grades of organization ter- Bility of the elastic ligaments and joint-structures minating in the highest dicotyledons and of a feline foot, for example, being superinduced mammals; second, of external physical cir- upon the more simple structure of the toe with cumstances, operating re-actively upon the the non-retractile claw, according to the princentral impulse to produce the requisite pe- ciple of a succession of varieties in time." t culiarities of exterior organization, the This very writer has, however, himself adaptation of the natural theologian." But he, likewise, requires the same additional element which Mr. Darwin so freely invokes. "The gestation of a single organism is the Vestiges," to produce the teleological adapwork of but a few days, weeks, or months; tations. Professor Owen has pointed out but the gestation (so to speak) of a whole the numerous instances in the animal kingcreation is a matter involving enormous dom of a principle of structure prevalent spaces of time."... "Though distinctions throughout the vegetable kingdom, exempliadmitted as specific are not now, to ordinary fied by the multiplication of organs in one observation, superable, time may have a animal performing the same function, and power over these." Geology shows not related to each other by combination of successions of forms and grants enormous powers for the performance of a higher funcspaces of time within which we may believe tion. The invertebrate animals, according them to have changed from each other by to the professor, afford the most numerous the means which we see producing varieties. and striking illustrations of the principles Brief spaces of time admittedly sufficing to produce these so-called varieties, is it unrea*Vestiges of Creation, 8vo., 1846, p. 231. sonable to suppose that large spaces of time "On the Tendency of Species to form Varieties," etc., in Proceedings of the Linnean SociReports of the Juries Exhibition of the Works ety," 1858, p. 49. of All Nations, 8vo., 1852, p. 70. Address, p. 44.

66

suggested an operative cause in the development of organized beings of a different and opposite character to that conceived by

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which he has generalized as the "Law of that the more generalized structure is in a Irrelative Repetition." very significant degree, a characteristic of many extinct as compared with recent animals; and it may be readily conceived that specialization of structure would be the result of the progressive modification of any organ applied to a special purpose in the animal economy.

"We perceive," says he, "in the fact of the endoskeleton consisting of a succession of ments similarly composed-in the very power of enunciating special, general, and serial homologies an illustration of that law of vegetative or irrelative repetition, which is so much more conspicuously manifested by the segments of the We have cited these attempts to elucidate exoskeleton of the invertebrata: as, for ex- the nature of the organizing forces, to show ample, in the rings of the centipede and worm, the prevalent condition of the most advanced and in the more multiplied parts of the skeleton of the Echinoderms. The repetition of similar physiological minds in regard to the cause segments in the spinal column, and of similar of the successive introduction of distinct elements in a vertebral segment, is analogous to the repetition of similar crystals, as the result of the polarizing force in the growth of an inorganic body. Not only does the principle of vegetative repetition prevail more and more as we descend in the scale of animal life, but the forms of the repeated parts of the skeleton approach more and more to geometrical figures; as we see, for example, in the external skeletons of the echini and star-fishes; nay, the calcifying salt assumes the same crystalline figures which characterize it, when deposited and subject to the general polarizing force out of the organized body. Here, therefore, we have direct proof of the concurrence of such general all-pervading polarizing force, with the adaptive or special organizing force, in the development of an animal body." In addition, therefore, to the organizing principle, however explained, producing the special "adaptations," and admitted as the "second" power in the production of species by "Vestiges," Professor Owen states

"There appears also to be in counter-operation during the building up of such bodies, a general polarizing force, to the operation of which the similarity of forms, the repetition of parts, the signs of the unity of organization may be mainly ascribed; the platonic idea or specific organizing principle would seem," he adds, "to be in antagonism with the general polarizing force, and to subdue and mould it in subserviency to the exigencies of the resulting specific form."*

An index of the degree in which the polaric or irrelative repetitive force has operated is given by that character of the animal's organization which is expressed by the term of a more generalized structure." V. Baer pointed out that the structure was "more generalized," in the ratio of the proximity of the individual to the starting point of its existence. In proportion as the individual is subject to the action and re-action of surrounding influences, in other words, as it advances in life, does it acquire a more specialized structure-more decided specific and individual characters.† Owen has shown

Archetype of the Vertebrate Skeleton, 8vo, 1840, p. 171.

"The extent to which the resemblance, expressed by the term Unity of Organization,' may

species of plants and animals. Demaillet invoked the operation of the external influences or conditions of life, with consentaneous volitional efforts, in order to raise species in the scale, as the fish, e. g., into the bird. Buffon called in the same agency to lower the specics, by way of degeneration, as the bear, e. g., into the seal, and this outward influences the effects of increased into the whale.† Lamarck added to these or decreased use or action of parts. The Author of "Vestiges," availing himself of the ingenious illustration of a pre-ordained exception, occurring at remote intervals, to the ordinary course, derived by Babbage from the working of his calculating engine, threw out the suggestion of a like rare exception in the character of the offspring of a known species, and he cites the results of embryological studies, to show how such "monster," either by excess or defect, by arbe no monster in fact, but one of the prerest or prolongation of development, might ordained exceptions in the long series of natural operations, giving rise to the introduction of a new species. Owen applies the more recent discoveries of Parthenogenesis to the same mysterious problem. A polype, e. g., breaks up into a pile of medusa; "the indirect or direct action of the conditions of life" might tend to harden the integument and change the medusa into a star-fish. But he resists the seduction of possibilities, and governed by the extent of actual observation, says: "The first acquaintance with these marvels excited the hope that we were about to penetrate the mystery of the origin of species; but as far as observation has yet extended, the cycle of changes is definitely closed." ‡

Mr. Wallace calls attention to the "tre

be traced between the higher and lower organized animals, bears an inverse ratio to their approximation to maturity." (Owen, Lectures on Invertebrata, p. 645.)

Telliamed, ou Entretiens d'un Philosophe Indien avec un Missionaire François, Amsterdam, 8vo, 1748. Histoire Naturelle, etc., 4to, tom. XIV. 1766. Address to the British Association at Leeds,

1858, p. 27,

forcibly and truly expresses it, both species and genus; such are the elephant, rhinoceros, hippopotamus, giraffe, camel, lion, bear, and mole. † Palæontology has since re

mendous rate of increase in a few years from a single pair of birds producing two young ones each year, and this only four times in their life; in fifteen years such pair would have increased to nearly ten millions!"vealed the evidences of the true nature and The passenger-pigeon of the United States causes of the present seeming isolation of exemplifies such rate of increase, where con- some of these forms. genial food abounds. But, as a general rule, the animal population of a country is stationary, being kept down by a periodical deficiency of food, and other checks. Hence the struggle for existence; and the successful result of adapted organization and powers in a well-developed variety, which Mr. Darwin generalizes as "Natural Selection," and which Mr. Wallace † illustrates as follows:"An antelope with shorter or weaker legs must necessarily suffer more from the attacks of the feline carnivora; the passenger-pigeon with less powerful wings, would sooner or later be affected in its powers of procuring a regular supply of food." If, on the other hand, "any species should produce a variety having slightly increased powers of preserving existence, that variety must inevitably in time acquire a superiority in numbers." " During any change tending to render existence more difficult to a species, tasking its utmost powers to avoid complete extermination, those individuals forming the most feebly organized variety would suffer first; the same causes continuing the parent species would next suffer, would gradually diminish in numbers, and with a recurrence of similar unfavorable conditions, must soon become extinct. The superior variety would then alone remain,

and on a return to favorable circumstances

would rapidly increase in numbers and occupy the place of the extinct species and variety The variety would now have replaced the species of which it would be a more perfectly developed and a more highly organized form."§

Such evidences have been mainly operative with the later adopters and diffusers of Buffon's principle in the reduction of the number of primitive sources of existing species, and the contraction of the sphere of direct creative acts. Thus Lamarck ‡ reduces the primordial forms or prototypes of animals to two, viz. the worm (vers), and the monad (infusoires); the principles which in the course of illimited time operated, on his hypothesis, to produce the present groups of animals led from the vibrio, through the annelids, cirripeds, and molluscs to fishes, and there met the other developmental route by way of rotifers, polypes, radiaries, insects, arachnides, and crustacea. The class of fishes, deriving its several forms from combinations of transmuted squids and crabs, then proceeded through the well-defined vertebrate pattern up to man. With a philosophic consistency, wanting in his latest follower, Lamarck sums up: d'animaux commençant par deux branches où se trouvent les plus imparfaits, les premiers de chacune de ces branches ne reçoivent l'existence que par génération directe ou spontanée." §

"Cette série

exact ideas of the affinities and relationships Mr. Darwin, availing himself of the more of animal groups obtained by subsequent induction, says: "I believe that animals have descended from at most only four or five progenitors," [evidently meaning, or answerBuffon regarded varieties as particular al- ing to, the type forms of the four or five terations of species, as supporting and illus-"sub-kingdoms" in modern zoology], “and trating a most important principle-the mu- plants from an equal or lesser number." tability of species themselves. The so-called But if the means which produce varieties varieties of a species, species of a genus, genera of a family, etc., were, with him, so many evidences of the progressive amount or degrees of change which had been superinduced by time and generations upon a primordial type of animal. Applying this principle to the two hundred mammalian species of which he had given a history in his great work, he believed himself able to reduce them to a very small number of primitive stocks or families. Of these he enumerates fifteen besides which, Buffon specifies certain isolated forms, which represent, as he *Proceedings of the Linnæan Society, 1858, p.

55.

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have operated "through the enormous species of time, within which species are changed," || the minor modifications which produce, under our brief scope of observation, so-called varieties, might well amount to differences equivalent to those now separating sub-kingdoms; and, accordingly, "analogy," Mr. Darwin logically admits, "would lead us one step further, namely, to the belief that all animals and plants have descended from some one prototype;" and summing up the conditions which all living things have

*"Quelques espèces isolées, qui, comme celle de l'homme, fassent en même temps espèce et genre."-Tom. cit. p. 335.

† Ib., p. 360.

Philosophie Zoologique, vol. ii. p. 463.
Ib., p. 463.

Vestiges of Creation, p. 231.

TOp. cit., p. 484.

in common, this writer infers from that analogy, that probably all the organic beings which have ever lived on this earth, have descended from some one primordial form, into which life was first breathed." *

By the latter scriptural phrase, it may be inferred that Mr. Darwin formally recognizes, in the so-limited beginning, a direct creative act, something like that supernatural or miraculous one which, in the preceding page, he defines, as "certain elemental atoms which have been commanded suddenly to flash into living tissues." He has, doubtless, framed in his imagination some idea of the common organic prototype; but he refrains from submitting it to criticism. He leaves us to imagine our globe void, but so advanced as to be under the conditions which render life possible; and he then restricts the Divine power of breathing life into organic form to its minimum of direct operation. All subsequent organisms henceforward result from properties imparted to the organic elements at the moment of their creation, pre-adapting them to the infinity of complications and their morphological results, which now try to the utmost the naturalist's faculties to comprehend and classify. And we admit with Buckland, that such an aboriginal constitution, "far from superseding an intelligent agent, would only exalt our conceptions of the consummate skill and power, that could comprehend such an infinity of future uses, under future systems, in the original groundwork of his creation." We would accordingly assure Professor Owen that he "may conceive the existence of such ministers, personified as nature without derogation of the Divine power;" and that he, with other inductive naturalists, may confidently advance in the investigation of those "natural laws or secondary causes, to which the orderly succession and progression of organic phenomena have been committed." We have no sympathy whatever with biblical objectors to creation by law, or with the sacerdotal revilers of those who would explain such law. Literal scripturalism in the time of Lactantius, opposed and reviled the demonstrations of the shape of the earth; in the time of Galileo it reviled and persecuted the demonstrations of the movements of the earth; in the time of Dean Cockburn of York, it anathematized the demonstrations of the antiquity of the earth; and the eminent geologist who then personified the alleged anti-scriptural heresy, has been hardly less emphatic than his theological assailant, in his denunciations of some of the upholders of the "becoming and succession of species by natural law," or by Op. cit., p. 484.

† On the Nature of Limbs, p. 86.

"a continuously operating creative force." What we have here to do, is to express our views of the hypothesis as to the nature and mode of operation of the creative law, which has been promulgated by Messrs. Wallace and Darwin.

The author of the volume "On the Origin of Species," starts from a single supernaturally created form. He does not define it; it may have been beyond his power of conception. It is, however, eminently plastic, is modified by the influence of external circumstances, and propagates such modifica- | tions by generation. Where such modified descendants find favorable conditions of existence, there they thrive; where otherwise they perish. In the first state of things, the result is so analogous to that which man brings about, in establishing a breed of domestic animals from a selected stock, that it suggested the phrase of "Natural Selection;" and we are appealed to, or at least "the young and rising naturalists with plastic minds, are adjured to believe that the reciprocal influences so defined have operated through divergence of character and extinction, on the descendants of a common parent, so as to produce all the organic beings that live, or have ever lived on our planet.

Now we may suppose that the primeval prototype began by producing in the legal generative way, creatures like itself, or so slightly affected by external influences, as at first to be scarcely distinguishable from their parent. When as the progeny multiplied and diverged, they came more and more under the influence of "Natural Selection," so, through countless ages of this law's operation, they finally rose to man. But, we may ask, could any of the prototype's descendants utterly escape the surrounding influences? To us such immunity, in the illimitable period during which the hypothesis of natural selection requires it to have operated, is inconceivable. No living being, therefore, can now manifest the mysterious primeval form to which Darwin restricts the direct creative act; and we may presume that this inevitable consequence of his hypothesis, became to him an insuperable bar to the definition of that form.

But do the facts of actual organic nature square with the Darwinian hypothesis? Are all the recognized organic forms of the present date so differentiated, so complex, so superior to conceivable primordial simplicity of form and structure, as to testify to the effects of natural selection continuously operating through untold time? Unquestionably not. The most numerous living beings now on the globe are precisely those which offer such a simplicity of form and *On the Nature of Limbs, p. 482.

structure, as best agrees, and we take leave to affirm can only agree, with that ideal prototype from which, by any hypothesis of natural law, the series of vegetable and animal life might have diverged.

If by the patient and honest study and comparison of plants and animals, under their manifold diversities of matured form, and under every step of development by which such form is attained, any idea may be gained of a hypothetical primitive organism,-if its nature is not to be left wholly to the unregulated fancies of dreamy speculation-we should say that the form and condition of life which are common, at one period of existence, to every known kind and grade of organism, would be the only conceivable form and condition of the one primordial being from which "Natural Selection "infers that all the organisms which have ever lived on this earth have descended.

All these would be interpreted as the earliest evidences of the modifying and species-changing influences, according to the hypothesis of Lamarck. They are the organisms respecting which the first living physiologists hesitate to apply the Harveian axiom omne vivum ab ovo, believing the possibility of their spontaneous origin to be by no means experimentally disproved. The prevalence of the essential first step in the production of all higher organisms, viz. through the combined matter of the "germcell" and "sperm-cell," has no doubt strongly inclined physiologists to believe impregna-j tion to be an absolute condition of the be-" ginning of all existing organisms. But, as the president of the British Association stated, in his "Address" at Leeds :

The

"In regard to lower living things, analogy is but hazardous ground for conclusions. Now the form in question is the nucleated single-celled organisms, such as many of the socalled animalcules of infusions, which are at a cell, having the powers of receiving nutri-stage of organization too low for a definite transtive matter from without, of assimilating fer to either the vegetable or animal kingdoms, such nutriment, and of propagating its kind offer a field of observation and experiment which by spontaneous fission. These powers are may yet issue in giving us a clearer insight into called "vital," because as long as they are the development of the organic living cell.'continued the organism is said to live. TheWhether an independent free-moving and asmost numerous and most widely diffused of living beings present this primitive grade of structure and vital force, which grade is inferior to that of the truly definable "plant" or "animal," but is a grade represented and passed through by the germ of every, even the highest, class of animals, in the course of embryonic development. The next stages of differentiated or advanced organization are defined as follows in Professor Owen's last publication :

similating organism, of a grade of structure similar to, and scarcely higher than, the "germcell," may not arise by a collocation of particles, that which originally formed the germ-cell in the through the operation of a force analogous to ovarian stroma, is a question which cannot be answered until every possible care and pains have been applied to its solution." "-P. 28.

Professor Pouchet believes that he is au

thorized by the results of his experiments to answer that question in the affirmative. It is one of supreme importance, and which "When the organism is rooted, has neither has, hitherto, never received such an amount mouth nor stomach, exhales oxygen, and has of painstaking experimental research as it tissues composed of cellulose' or of binary or merits; and the best observations, the most ternary compounds, it is called a plant.' carefully conducted and ingeniously devised When the organism can move, when it receives arrangements for insuring success, are unthe nutritive matter by a mouth, inhales oxygen, doubtedly those of the patiently observant and exhales carbonic acid, and develops tis-professor of Zoology in the "Ecole de Médsues, the proximate principles of which are quaternary compounds of carbon, hydrogen, ecine," and "Ecole supérieure des Sciences," oxygen, and nitrogen, it is called an animal.' at Rouen.* This, at least, may be affirmed, But the two divisions of organisms called 'plants' and 'animals' are specialized members of the great natural groups of living things; and there are numerous organisms, mostly of minute size and retaining the form of nucleated cells, which manifest the common organic characters, but without the distinctive superadditions of true plants or animals. Such organisms are called protozoa,' and include the sponges or Amorphozoa, the Foraminifera or Rhizopods, the Polycystine, the Diatomacea, Desmidia, Gregarina, and most of the so-called Polygastria of Ehrenberg, or infusorial animalcules of older authors."*

* Owen's Paleontology, p. 4.

that the inductive groundwork of his opponents is by no means such as can justify any dogmatic negation of Heterogeny as appli cable to the simplest Protozoa.

On the basis, therefore, of analogical probability, it may be inferred:-that the primordial as well as all other forms of organic beings, originate, and have ever originated, from the operation of secondary and continuously operating creative laws: and that the various grades of organisms now in being,

* Pouchet, "Hétérogénie, ou Traité de la Génération spontanée, basé sur des nouvelles Expériences," Svo., 1859.

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