[50] Journ. Linn. Soc. London (Zool.), Vol. xxvi. 1898, pp. 598-602.
[51] In Kosmos, 1879, p. 100.
[52] Habit and Instinct, London. 1896.
[53] This has been discussed in many of my earlier works. See for instance The All-Sufficiency of Natural Selection, a reply to Herbert Spencer, London, 1893.
[54] The Evolution Theory, London, 1904, p. 144.
[55] Variation under Domestication, 1875, ii. pp. 426, 427.