[160] Origin of Species (6th edit.), p. 205.
[161] Ibid. p. 233.
[162] Ibid. p. 205.
[163] Origin of Species (6th edit.), p. 233.
[164] Origin of Species, pp. 210, 211.
[165] Independently suggested, on somewhat different lines, by Profs. J. Mark Baldwin, Henry F. Osborn and the writer.
[166] Origin of Species (6th edit.), p. 206.
[167] Expression of the Emotions, p. 13. The passage is here somewhat condensed.
[168] Ibid. p. 368.
[169] Expression of the Emotions, pp. 373, 374.