[172] In Popular Science Monthly, April, 1909, vol. LXXIV, p. 396.
[173] To Wallace, April 20, 1870, Life, vol. II, p. 301.
[174] Darwiniana, p. 286.
[175] Animals and Plants, vol. I, p. 225.
[176] Descent, p. 563.
[177] More Letters, vol. I, p. 2.
[178] Life, vol. I, p. 54.
[179] To Hooker, November 5, 1854, Life, vol. I, p. 404.
[180] To Hooker, July 13, 1858, Life, vol. I, p. 484.
[181] Life, vol. I, p. 46.