B
Baker, Mr. J.G., on rarity of spiny plants in Mauritius, 432
Ball, Mr., on cause of late appearance of exogens, 400
Barber, Mrs., on variable colouring of pupae of Papilio nireus, 197
on protective colours of African sun-birds, 200
Barbs, 91
Barriers, importance of, in questions of distribution, 341
Bates, Mr. H.W., on varieties of butterflies, 44
on inedibility of Heliconidæ, 234
on a conspicuous caterpillar, 236
on mimicry, 240, 243, 249
Bathmism or growth-force, Cope on, 421
Beddard, Mr. F.E., variations of earthworms, 67
on plumes of bird of paradise, 292
Beech trees, aggressive in Denmark, 21
Beetle and wasp (figs.), 259
Beetle, fossil in coal measures of Silesia, 404
Beginnings of important organs, 128
Belt, Mr., on leaf-like locust, 203
on birds avoiding Heliconidæ 234
Belt's frog, 266
Birds, rate of increase of, 25
how destroyed, 26
variation among, 49
variation of markings of, 52
variation of wings and tails of, 53
diagram showing variation of tarsus and toes, 60
use of structural peculiarities of, 135
eggs, coloration of, 212
recognition marks of, 222
and butterflies, white in tropical islands, 230
sometimes seize inedible butterflies, 255
mimicry among, 263
Birds, sexual coloration of, 275
cause of dull colour of female, 277
choice of female not known to be determined by colour, etc., 285
decorative plumage of, 285
antics of unornamented, 287
which fertilise flowers, 319
colours of, not dependent on the colours of flowers, 336
no proof of aesthetic tastes in, 336
dispersal of, 355
and insects at sea, 357
of oceanic islands, 358
carrying seeds on their feet, 361
ancestral forms of, 407
Birthplace, probable, of man, 459
Bombyx regia, protective form of larva of, 210
Boyd Dawkins, on development of deer's horns, 389
on origin of man, 456
Brady, Mr. George, on protective colouring of starfishes, 209
Brain development, progressive, 390
Brains of man and apes, 452
Branner, Mr. J.C., on supposed proofs of glaciation in Brazil, 370
Brazil, supposed proof of glaciation in, 370
Brewer, Professor W.H., on want of symmetry in colours of animals, 217
Bromelia, animals inhabiting leaves of, 118
Bronn, Professor, on supposed uselessness of variations of ears and tails, 136
Butler, Mr. A.G., on inedibility of conspicuous caterpillars, 237
Butterflies, varieties of, 44
small, of Isle of Man, 106
special protective colouring of, 206
recognition by, 226
inedibility of some, 234
mimicry among, 240, 249
colour development of, 274
sexual coloration of, 271
