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modern times has treated it in a scientific spirit was Buffon. But as his opinions fluctuated greatly at different periods, and as he does not enter on the causes or means of the transformation of species, I need not here enter on details. Lamarck was the first man whose conclusions on the subject excited much attention. This justly-celebrated naturalist first published his views in 1801; he much enlarged them in 1809 in his Philosophie Zoologique,” and subsequently, in 1815, in the Introduction to his * Hist. Nat. des Animaux sans Vertébres.” In these works he upholds the doctrine that all species, including man, are descended from other species. He first did the eminent service of arousing attention to the probability of all change in the organic, as well as in the inorganic world, being the result of law, and not of miraculous interposition. Lamarck seems to have been chiefly led to his conclusion on the gradual change of species, by the difficulty of distinguishing species and varieties, by the almost perfect gradation of forms in certain groups, and by the analogy of domestic productions. With respect to the means of modification, he attributed something to the direct action of the physical conditions of life, something to the crossing of already existing forms, and much to use and disuse, that is, to the effects of habit. To this latter agency he seems to attribute all the beautiful adaptations in nature;—such as the long neck of the giraffe for browsing on the

by an internal spontaneity; and whatsoever things were not thus

constituted, perished, and still perish.” We here see the principle

of natural selection shadowed forth, but how little Aristotle fully

comprehended the principle, is shown by his remarks on the formation of the teeth.

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branches of trees. But he likewise believed in a law of progressive development; and as all the forms of life thus tend to progress, in order to account for the existence at the present day of simple productions, he maintains that such forms are now spontaneously generated” Geoffroy Saint-Hilaire, as is stated in his ‘Life,’ written by his son, suspected, as early as 1795, that what we call species are various degenerations of the same type. It was not until 1828 that he published his conviction that the same forms have not been perpetuated since the origin of all things. Geoffroy seems to have relied chiefly on the conditions of life, or the “monde ambiant ’’ as the cause of change. He was cautious in drawing conclusions, and did not believe that existing species are now undergoing modification; and, as his son adds, “ C'est done un problème a réserver entièrement à l'avenir, supposé méme que l'avenir doive avoir prise sur lui.” In 1813, Dr. W. C. Wells read before the Royal Society “An Account of a White female, part of whose skin resembles that of a Negro'; but his paper was not published until his famous ‘Two Essays upon Dew and Single Vision appeared in 1818. In this paper he distinctly recognises the principle of natural selection, and this is the first recognition which has been indicated; but he applies it only to the races of man, and to certain characters alone. After remarking that negroes and mulattoes enjoy an immunity from certain tropical diseases, he observes, firstly, that all animals tend to vary in some degree, and, secondly, that agriculturists improve their domesticated animals by selection; and then, he adds, but what is done in this latter case “by art, seems to be done with equal efficacy, though more slowly, by nature, in the formation of varieties of mankind, fitted for the country which they inhabit. Of the accidental varieties of man, which would occur among the first few and scattered inhabitants of the middle regions of Africa, some one would be better fitted than the others to bear the diseases of the country. This race would consequently multiply, while the others would decrease; not only from their inability to sustain the attacks of disease, but from their incapacity of contending with their more vigorous neighbours. The colour of this vigorous race I take for granted, from what has been already said, would be dark. But the same disposition to form varieties still existing, a darker and a darker race would in the course of time occur: and as the darkest would be the best fitted for the climate, this would at length become the most prevalent, if not the only race, in the particular country in which it had originated.” He then extends these same views to the white inhabitants of colder

* I have taken the date of the first publication of Lamarck from Isid. Geoffroy Saint-Hilaire's (“Hist. Nat. Générale, tom. ii. p. 405, 1859) excellent history of opinion on this subject. In this work a full account is given of Buffon's conclusions on the same subject. It is curious how largely my grandfather, Dr. Erasmus Darwin, anticipated the views and erroneous grounds of opinion of Lamarck in his Zoonomia' (vol. i. pp. 500-510), published in 1794. According to Isid. Geoffroy there is no doubt that Goethe was an extreme partisan of similar views, as shown in the Introduction to a work written in 1794 and 1795, but not published till long afterwards: he has pointedly remarked (“Goethe als Naturforscher, von Dr. Karl Meding, s. 34) that the future question for naturalists will be how, for instance, cattle got their horns, and not for what they are used. It is rather a singular instance of the manner in which similar views arise at about the same time, that Goethe in Germany, Dr. Darwin in England, and Geoffroy SaintHilaire (as we shall immediately see) in France, came to the same conclusion on the origin of species, in the years 1794–5.

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climates. I am indebted to Mr. Rowley, of the United
States, for having called my attention, through Mr.
Brace, to the above passage in Dr. Well’s work.
The Hon. and Rev. W. Herbert, afterwards Dean of
Manchester, in the fourth volume of the Horticultural
Transactions,’ 1822, and in his work on the “Amaryl-
lidaceae (1837, pp. 19, 339), declares that “horticultural
experiments have established, beyond the possibility of
refutation, that botanical species are only a higher and
more permanent class of varieties.” He extends the
same view to animals. The Dean believes that single
species of each genus were created in an originally
highly plastic condition, and that these have produced,
chiefly by intercrossing, but likewise by variation, all
our existing species.
In 1826 Professor Grant, in the concluding para-
graph in his well-known paper (; Edinburgh Philosophi-
cal Journal, vol. xiv. p. 283) on the Spongilla, clearly
declares his belief that species are descended from other
species, and that they become improved in the course of
modification. This same view was given in his 55th
Lecture, published in the ‘Lancet’ in 1834.
In 1831 Mr. Patrick Matthew published his work on
‘Naval Timber and Arboriculture, in which he gives
precisely the same view on the origin of species as that
(presently to be alluded to) propounded by Mr. Wallace
and myself in the Linnean Journal, and as that en-
larged in the present volume. Unfortunately the view
was given by Mr. Matthew very briefly in scattered
passages in an Appendix to a work on a different sub-
ject, so that it remained unnoticed until Mr. Matthew
himself drew attention to it in the ‘Gardener’s

Chronicle, on April 7th, 1860. The differences of Mr.

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Matthew’s view from mine are not of much importance: he seems to consider that the world was nearly depopulated at successive periods, and then re-stocked; and he gives as an alternative, that new forms may be generated “without the presence of any mould or germ of former aggregates.” I am not sure that I understand SOIme passages; but it seems that he attributes much influence to the direct action of the conditions of life. He clearly saw, however, the full force of the principle of natural selection. The celebrated geologist and naturalist, Von Buch, in his excellent Description Physique des Isles Canaries’ (1836, p. 147), clearly expresses his belief that varieties slowly become changed into permanent species, which are no longer capable of intercrossing. Rafinesque, in his ‘New Flora of North America.’ published in 1836, wrote (p. 6) as follows:– “All species might have been varieties once, and many varieties are gradually becoming species by assuming constant and peculiar characters; ” but farther on (p. 18) he adds, “except the original types or ancestors of the genus.” In 1843–44 Professor Haldeman (‘Boston Journal of Nat. Hist. U. States, vol. iv. p. 468) has ably given the arguments for and against the hypothesis of the development and modification of species: he seems to lean towards the side of change. The Vestiges of Creation appeared in 1844. In the tenth and much improved edition (1853) the anonymous author says (p. 155):-" The proposition determined on after much consideration is, that the several series of animated beings, from the simplest and oldest up to the highest and most recent, are, under the

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