ii. 52;

on rivalry in song-birds, ii. 53; on the singing of female birds, ii. 54; on birds acquiring the songs of other birds, ii. 55; on pairing the canary and siskin, ii. 115; on a sub-variety of the monk pigeon, ii. 132; on spurred hens, ii. 162.

BEDDOE, Dr., on causes of difference in stature, i. 115.

BEE-EATER, ii. 56.

BEES, i. 73; destruction of drones and queens by, i. 82; pollen-baskets and stings of, i. 155; female, secondary sexual characters of, i. 254; difference of the sexes in, i. 365.

BEETLE, luminous larva of a, i. 345.

BEETLES, i. 366; size of the cerebral ganglia in, i. 145; dilatation of the fore tarsi in male, i. 343; blind, i. 367; stridulation of, i. 378.

BELGIUM, ancient inhabitants of, i. 237.

BELL, Sir C, on emotional muscles in man, i. 5; "snarling muscles," i. 127; on the hand, i. 141.

BELL, T., on the numerical proportion of the sexes in moles, i. 305; on the newts, ii. 24; on the croaking of the frog, ii. 27; on the difference in the coloration of the sexes in _Zootoca vivipara_, ii. 36; on moles fighting, ii. 239.

BELL-BIRD, sexual difference in the colour of the, ii. 79.

BELL-BIRDS, colours of, ii. 228.

BENEVOLENCE, manifested by birds, ii. 109.

BENNETT, A. W., on the habits of _Dromoeus irroratus_, ii. 205.

BENNETT, Dr., on birds of paradise, ii. 89.

_Bernicla antarctica_, colours of, ii. 228.

BERNICLE gander pairing with a Canada goose, ii. 114.

BETTONI, E., on local differences in the nests of Italian birds, ii, 171.

BHOTEAS, colour of the beard in, ii. 319.

_Bhringa_, disciform tail-feathers of, ii. 83.

_Bibio_, sexual differences in the genus, i. 349.

BICHAT, on beauty, ii. 354.

BILE, coloured, in many animals, i. 323.

BIMANA, i. 190.

BIRDS, imitations of the songs of other birds by, i. 44; dreaming, i. 46; language of, i. 55; sense of beauty in, i. 63; pleasure of, in incubation, i. 79; male, incubation by, i. 210; and reptiles, alliance of, i. 213; sexual differences in the beak of some, i. 255; migratory, arrival of the male before the female, i. 259; apparent relation between polygamy and marked sexual differences in,