The Darwinian theory of the transmutation of species / examined by a graduate of the University of Cambridge.

  • Beverley, R. M. (Robert Mackenzie), 1797 or 1798-1868.
Date:
1867
Catalogue details

Licence: Public Domain Mark

Credit: The Darwinian theory of the transmutation of species / examined by a graduate of the University of Cambridge. Source: Wellcome Collection.

    50/408 (page 34)
    most important consideration—new races of animals and plants are produced under domestication by man’s methodi- cal and unconscious power of selection’ (291); and yet the varieties of the dog are not to be accounted for in this way, but by having originally sprung from distinct species. To us, however, BufFon’s reasoning on the subject is satisfac- tory, and he seems to have established the probability that the shepherd’s dog is the c vrai chien de la nature; ’ the dog that prevails in various parts of the world with the same character, and a similar form, and constitutes in fact ‘ the stock and the model of the entire species ’—‘ lasouche et le modele de l’espece entiered What then is the general result of all that has been ad- vanced to forward the theory ? Truly, we may say, almost nothing. Much is urged about the contradictory evidence afforded us by plants — species that can be united with facility producing hybrids £ remarkably sterile ’ — species crossed with difficulty, but with a hybrid progeny when £at last produced,’ fertile. We are told that hybrids never have been raised between species ranked by systematists in distinct families; and a multitude of cases could be given of very closely allied species, which will not unite, or only with extreme difficulty (279); and all this we should have thought tends to prove the case against the theory. But the conclusion with Mr Darwin is in these words : £ Do these singular and complex rules indicate that species has been endowed with sterility simply to prevent their be- coming confounded in nature ? I think not—to grant to species the special power of producing hybrids, and then to stop their further propagation by different degrees of sterility, not strictly related to the facility of the first