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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 organisation and powers in a well developed variety, which Mr. Darwin generalises as Natural Selection,' and which Mr. Wallace illustrates as follows:

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'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 organised 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 unfavourable conditions, must soon become extinct. The superior variety would then alone remain, and on a return to favourable 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 organised form.' +

Buffon regarded varieties as particular alterations of species, as supporting and illustrating a most important principle - the mutability of species themselves. The so-called varieties of a species, species of a genus, genera of a family, &c., 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 forcibly and truly expresses it, both species and genus : such are the elephant, rhinoceros, hippopotamus, giraffe, camel, lion, bear, and mole.

Proceedings of the Linnean Society (dated from 'Ternate,' February 1858), vol. iii. p. 58.

† Wallace, loc. cit. p. 85.

§ Histoire Naturelle tom. xiv. p. 338.

+ Ib., p. 58.

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

Ib., p. 360.

Paleontology has since revealed the evidences of the true nature and causes of the present seeming isolation of some of these forms.

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: Cette série '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.'†

Mr. Darwin, availing himself of the more exact ideas of the affinities and relationships 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 answering to, the type-forms of the four or five 'sub-kingdoms' in modern zoology], and plants from an equal or lesser

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'number.'

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But if the means which produce varieties 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 subkingdoms; 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 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.

* Philosophie Zoologique, vol. ii. p. 463. Vestiges of Creation, p. 231.

† Ib., p. 463.

§ Op. cit., p. 484.

Ib.

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Darwin formally recognises, in the so-limited beginning, a direct creative act, something like that supernatural or miraculous one which, in the preceding page, he defines, ascertain 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 anathematised the demonstrations of the antiquity of the earth; and the eminent geologist who then personified the alleged antiscriptural 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 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.

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The author of the volume 'On the Origin of Species,' starts

On the Nature of Limbs, p. 86.

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 modifications by generation. Where such modified descendants find favourable 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 recognised 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. Unquestionably not. The most numerous living beings now on the globe are precisely those which offer such a simplicity of form and 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

* On the Nature of the Limbs, p. 482.

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.

Now the form in question is the nucleated cell, having the powers of receiving nutritive matter from without, of assimilating such nutriment, and of propagating its kind by spontaneous fission. These powers are called vital,' because as long as they are continued the organism is said to live. The most 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 organisation are defined as follows in Professor Owen's last publication:

'When the organism is rooted, has neither mouth nor stomach, exhales oxygen, and has tissues composed of "cellulose" or of binary or ternary compounds, it is called a "plant." When the organism can move, when it receives the nutritive matter by a mouth, inhales oxygen, and exhales carbonic acid, and developes tissues, the proximate principles of which are quaternary compounds of carbon, hydrogen, oxygen, and nitrogen, it is called an "animal." But the two divisions of organisms called "plants" and "animals" are specialised 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 Polycystinea, the Diatomacea, Desmidiæ, Gregarine, and most of the so-called Polygastria of Ehrenberg, or infusorial animalcules of older authors.'

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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

* Owen's Paleontology, p. 4.

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