[160] Hewitt on wild ducks, ‘Journal of Horticulture,’ Jan. 13, 1863, p. 39. Audubon on the wild turkey, ‘Ornith. Biography,’ vol. i. p. 14. On the mocking thrush, ibid. vol. i. p. 110. [161] The ‘Ibis,’ vol. ii. 1860, p. 344. [162] On the ornamented nests of humming-birds, Gould, ‘Introduction to the Trochilidæ,’ 1861, p. 19. On the bower-birds, Gould, ‘Handbook to the Birds of Australia,’ 1865, vol. i. p. 444-461. Mr. Ramsay in the ‘Ibis,’ 1867, p. 456. [163] ‘Hist. of British Birds,’ vol. ii. p. 92. [164] ‘Zoologist,’ 1853-1854, p. 3946. [165] Waterton, ‘Essays on Nat. Hist.’ 2nd series, p. 42, 117. For the following statements, see on the wigeon, Loudon’s ‘Mag. of Nat. Hist.’ vol. ix. p. 616; L. Lloyd, ‘Scandinavian Adventures,’ vol. i. 1854, p. 452; Dixon, ‘Ornamental and Domestic Poultry,’ p. 137; Hewitt, in ‘Journal of Horticulture,’ Jan. 13, 1863, p. 40; Bechstein. ‘Stubenvögel,’ 1840, s. 230. [166] Audubon, ‘Ornitholog. Biography,’ vol. i. p. 191, 349; vol. ii. p. 42, 275; vol. iii. p. 2. [167] ‘Rare and Prize Poultry,’ 1854, p. 27. [168] ‘The Variation of Animals and Plants under Domestication,’ vol. ii. p. 103. [169] Boitard and Corbié, ‘Les Pigeons,’ 1824, p. 12. Prosper Lucas (‘Traité de l’Héréd. Nat.’ tom. ii. 1850, p. 296) has himself observed nearly similar facts with pigeons. [170] ‘Die Taubenzucht,’ 1824, s. 86. [171] ‘Ornithological Biography,’ vol. i. p. 13. [172] ‘Proc. Zool. Soc.’ 1835, p. 54. The japanned peacock is considered by Mr. Sclater as a distinct species, and has been named _Pavo nigripennis_. [173] Rudolphi, ‘Beyträge zur Anthropologie,’ 1812, s. 184. [174] ‘Die Darwin’sche Theorie, und ihre Stellung zu Moral und Religion,’ 1869, s. 59. [175] In regard to peafowl, see Sir R. Heron, ‘Proc. Zoolog. Soc.’ 1835, p. 54, and the Rev. E. S. Dixon, ‘Ornamental Poultry,’ 1848, p. 8. For the turkey, Audubon, ibid. p. 4. For the capercailzie, Lloyd, ‘Game Birds of Sweden,’ 1867, p. 23. [176] Mr. Hewitt, quoted in ‘Tegetmeier’s Poultry Book,’ 1866, p. 165. [177] Quoted in Lloyd’s ‘Game Birds of Sweden,’ p. 345. [178] According to Dr. Blasius (‘Ibis,’ vol. ii. 1860, p. 297), there are 425 indubitable species of birds which breed in Europe, besides 60 forms, which are frequently regarded as distinct species. Of the latter, Blasius thinks that only ten are really doubtful, and that the other fifty ought to be united with their nearest allies; but this shews that there must be a considerable amount of variation with some of our European birds. It is also an unsettled point with naturalists, whether several North American birds ought to be ranked as specifically distinct from the corresponding European species.