Births, numerical proportions of the sexes in, in animals and man; male
and female, numerical proportion of, in England.
Bischoff, Prof., on the agreement between the brains of man and of the
orang; figure of the embryo of the dog; on the convolutions of the
brain in the human foetus; on the difference between the skulls of man
and the quadrumana; resemblance between the ape s and man s.
Bishop, J., on the vocal organs of frogs; on the vocal organs of
cervine birds; on the trachea of the Merganser.
Bison, American, co-operation of; mane of the male.
Bitterns, dwarf, coloration of the sexes of.
Biziura lobata, musky odour of the male; large size of male.
Blackbird, sexual differences in the; proportion of the sexes in the;
acquisition of a song by; colour of the beak in the sexes of the;
pairing with a thrush; colours and nidification of the; young of the;
sexual difference in coloration of the.
Black-buck, Indian, sexual difference in the colour of the.
Blackcap, arrival of the male, before the female; young of the.
Black-cock, polygamous; proportion of the sexes in the; pugnacity and
love-dance of the; call of the; moulting of the; duration of the
courtship of the; and pheasant, hybrids of; sexual difference in
coloration of the; crimson eye-cere of the.
Black-grouse, characters of young.
Blacklock, Dr., on music.
Blackwall, J., on the speaking of the magpie; on the desertion of their
young by swallows; on the superior activity of male spiders; on the
proportion of the sexes in spiders; on sexual variation of colour in
spiders; on male spiders.
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