i. 104;

on hereditary genius, i. 111; on the effects of natural selection on civilised nations, i. 168; on the sterility of sole daughters, i. 170; on the degree of fertility of people of genius, i. 171; on the early marriages of the poor, i. 173; on the ancient Greeks, i. 177; on the Middle Ages, i. 178; on the progress of the United States, i. 179; on South African notions of beauty, ii. 347.

_Gammarus_, use of the chelae of, i. 331.

_Gammarus marinus_, i. 334.

GANNETS, white only when mature, ii. 228.

GANOIDEI, i. 204.

GANOID fishes, i. 212.

GAOUR, horns of the, ii. 247.

GAP between man and the apes, i. 200.

GAPER, sexes and young of, ii. 217.

GARDNER, on an example of rationality in a _Gelasimus_, i. 334.

_Garrulus glandarius_, ii. 104.

GAERTNER, on sterility of hybrid plants, i. 223.

GASTEROPODA, i. 324; pulmoniferous, courtship of, i. 324.

_Gasterosteus_, i. 271; nidification of, ii. 20.

_Gasterosteus leiurus_, ii. 2, 14, 20.

_Gasterosteus trachurus_, ii. 2.

_Gastrophora_, wings of, brightly coloured beneath, i. 397.

GAUCHOS, want of humanity among the, i. 101.

GAUDRY, M., on a fossil monkey, i. 197.

_Gavia_, seasonal change of plumage in, ii. 228.

GEESE, clanging noise made by, ii. 51; pairing of different species of, ii. 114; Canada, selection of mates by, ii. 116.

GEGENBAUR, C., on the number of digits in the Ichthyopterygia,