CHAPTER XI

SEXUAL SELECTION AMONG ANIMALS

Mr. Darwin’s theory of ‘Sexual Selection,’ pp. 240, _et seq._—Contradiction between the theories of natural and sexual selection, pp. 241, _et seq._—The colours of flowers, pp. 242, _et seq._—Mr. Wallace’s theory of the sexual colours of animals, p. 243.—The sexual colours make it easier for the sexes to find each other, pp. 243, _et seq._—They occur exactly in those species whose habits and manner of living make these colours most visible, pp. 244, _et seq._—The odours of flowers, p. 246.—Sexual odours and sounds among animals, pp. 246, _et seq._—The sexual colours, odours, and sounds of animals complementary to each other in the way that is best suited to make the animals easily discoverable, pp. 247-249.—The untenableness of Mr. Darwin’s theory, p. 249.—The secondary sexual characters due to natural selection, pp. 249, _et seq._—Mr. Wallace’s views, p. 250.—Animal ‘ornaments,’ pp. 250, _et seq._—Further arguments against Mr. Darwin’s theory, p. 251.—The variability of the secondary sexual characters, pp. 251. _et seq._—Their stability in wild species, p. 252.