[Footnote 31: Darwin, _Animals and Plants under Domestication_, vol. i. p. 322.]
[Footnote 32: These facts are taken from Darwin's _Domesticated Animals and Cultivated Plants_, vol. i. pp. 359, 360, 392-401; vol. ii. pp. 231, 275, 330.]
[Footnote 33: See Darwin's _Animals and Plants under Domestication_, vol. i. pp. 40-42.]
[Footnote 34: Mr. Brent in _Journal of Horticulture_, 1861, p. 76; quoted by Darwin, _Animals and Plants under Domestication_, vol. i. p. 151.]
[Footnote 35: This account of domestic pigeons is greatly condensed from Mr. Darwin's work already referred to.]
[Footnote 36: _Animals and Plants under Domestication_, vol. ii. pp. 307-311.]
