Domestication, essential points in, ii. [405]-[406];

favourable to crossing, ii. [109]-[110];

fertility increased by, ii. [111]-[113], [174].

Domesticated animals, origin of, ii. [160]-[161];

occasional sterility of, under changed conditions, ii. [161]-[162].

Donders, Dr., hereditary hypermetropia, ii. [8].

Dorking fowl, i. 227, 261;

furcula of, figured, i. 268.

Dormouse, ii. [152].

Double flowers, ii. [167]-[168], [171]-[172];