[327] 'Cottage Gardener,' 1856, p. 186. For Mr. Robson's subsequent statements, see 'Journal of Horticulture,' Feb. 18, 1866, p. 121. For Mr. Abbey's remarks on grafting, &c., idem, July 18, 1865, p. 44.
[328] 'Mém. de l'Acad. des Sciences,' 1790, p. 209.
[329] 'On the Varieties of Wheat,' p. 52.
[330] Mr. Spencer has fully and ably discussed this whole subject in his 'Principles of Biology,' 1864, vol. ii. ch. x. In the first edition of my 'Origin of Species,' 1859, p. 267, I spoke of the good effects from slight changes in the conditions of life and from cross-breeding, and of the evil effects from great changes in the conditions and from crossing widely distinct forms, as a series of facts "connected together by some common but unknown bond, which is essentially related to the principle of life."
[331] 'Essais de Zoologie Générale,' 1841, p. 256.
[332] Du Rut, 'Annales du Muséum,' 1807, tom. ix. p. 120.
[333] 'Säugethiere von Paraguay,' 1830, s. 49, 106, 118, 124, 201, 208, 249, 265, 327.
[334] 'The Naturalist on the Amazons,' 1863, vol. i. pp. 99, 193; vol. ii. p. 113.
[335] 'Embassy to the Court of Ava,' vol. i. p. 534.
[336] 'Journal,' vol. i. p. 213.