i. 240;

practice of tattooing in, ii. 342; aversion of natives of, to hairs on the face, ii. 349; pretty girls engrossed by the chiefs in, ii. 369.

NEWTON, A., on the throat-pouch of the male bustard, ii. 58; on the difference between the females of two species of _Oxynotus_, ii. 193; on the habits of the phalarope, dotterel, and godwit, ii. 204.

NEWTS, ii. 24.

NICHOLSON, Dr., on the non-immunity of dark Europeans from yellow fever, i. 245.

NICTITATING membrane, i. 23, 207.

NIDIFICATION, of fishes, ii. 19; relation of, to colour, ii. 167, 172; of British birds, ii. 169.

NIGHT-HERON, cries of the, ii. 51.

NIGHTINGALE, arrival of the male before the female, i. 259; object of the song of the, ii. 52.

NIGHTINGALES, new mates found by, ii. 105.

NIGHTJAR, selection of a mate by the female, ii. 116; Australian, sexes of, ii. 206; coloration of the, ii. 226.

NIGHTJARS, noise made by some male, with their wings, ii. 62; elongated feathers in, ii. 73, 97.

NILGHAU, sexual differences of colour in the, ii. 287.

NILSSON, Prof., on the resemblance of stone arrow-heads from various places, i. 233; on the development of the horns in the reindeer, i. 288.

NIPPLES, absence of, in Monotremata, i. 209.

NITZSCH, C. L., on the down of birds, ii. 80.

NOCTUAE, brightly-coloured beneath, i. 397.

NOCTUIDAE, coloration of, i. 394.

NORDMANN, A., on _Tetrao urogalloides_, ii. 100.

NOMADIC habits, unfavourable to human progress, i. 167.

NORWAY, numerical proportion of male and female births in, i. 301.

NOSE, resemblance of, in man and the apes, i. 192; piercing and ornamentation of the, ii. 341; flattening of the, ii. 352; very flat, not admired in negroes, ii. 350.

NOTT and Gliddon, on the features of Rameses II., i. 217; on the features of Amunoph III., i. 218; on skulls from Brazilian caves, i. 218; on the immunity of negroes and mulattoes from yellow fever, i. 243; on the deformation of the skull among American tribes, ii. 352.

NUDIBRANCH mollusca, bright colours of, i. 326.

NUMERALS, Roman, i. 182.

NUNEMAYA, natives of, bearded, ii. 322, 349.

O.

OBEDIENCE, value of, i. 162.

OBSERVATION, powers of, possessed by birds, ii. 109.

OCCUPATIONS, sometimes a cause of diminished stature, i. 115; effect of, upon the proportions of the body, i. 116.

OCELLI, absence of, in female Mutillidae, i. 341.

OCELLI of birds, formation and variability of the, ii. 132.

OCELOT, sexual differences in the colouring of the, ii. 287.

_Ocyphaps lophotes_, ii. 96.

ODONATA, i. 314.

_Odonestis potatoria_, sexual difference of colour in, i. 398.

ODOUR, correlation of, with colour of skin, i. 248; emitted by snakes in the breeding-season, ii. 30; of mammals, ii. 278.

_Oecanthus nivalis_, difference of colour in the sexes of, i. 361.

_Oidemia_, ii. 226, 227.

OLIVIER, on sounds produced by _Pimelia striata_, i. 385.

_Omaloplia brunnea_, stridulation of, i. 381.

_Onitis furcifer_, processes of anterior femora of the male, and on the head and thorax of the female, i. 372.

_Onthophagus_, i. 370.

_Onthophagus rangifer_, sexual differences of, i. 369; variation in the horns of the male, i. 370.

OPHIDIA, sexual differences of, ii. 29.

OPOSSUM, wide range of, in America, i. 219.

OPTIC nerve, atrophy of the, caused by destruction of the eye, i. 116.

ORANG-OUTAN, ii. 323; Bischoff on the agreement of the brain of the, with that of man,