Nipples, absence of, in Monotremata.
Nitsche, Dr., ear of foetal orang.
Nitzsch, C.L., on the down of birds.
Noctuae, brightly-coloured beneath.
Noctuidae, coloration of.
Nomadic habits, unfavourable to human progress.
Nordmann, A., on Tetrao urogalloides.
Norfolk Island, half-breeds on.
Norway, numerical proportion of male and female births in.
Nose, resemblance of, in man and the apes; piercing and ornamentation of the; very flat, not admired in negroes; flattening of the.
Nott and Gliddon, on the features of Rameses II.; on the features of Amunoph III.; on skulls from Brazilian caves; on the immunity of negroes and mulattoes from yellow fever; on the deformation of the skull among American tribes.
Novara, voyage of the, suicide in New Zealand.
Nudibranch Mollusca, bright colours of.
Numerals, Roman.
Nunemaya, natives of, bearded.
Nuthatch, of Japan, intelligence of; Indian.
Obedience, value of.
Observation, powers of, possessed by birds.
Occupations, sometimes a cause of diminished stature; effect of, upon the proportions of the body.
Ocelli, absence of, in female Mutilidae.
Ocelli of birds, formation and variability of the.
Ocelot, sexual differences in the colouring of the.
Ocyhaps lophotes.
Odonata.
Odonestis potatoria, sexual difference of colour in.
Odour, correlation of, with colour of skin; of moths; emitted by snakes in the breeding season; of mammals.
Oecanthus nivalis, difference of colour in the sexes of.
Oecanthus pellucidus.
Ogle, Dr. W., relation between colour and power of smell.
Oidemia.
Oliver, on sounds produced by Pimelia striata.
Omaloplia brunnea, stridulation of.
Onitis furcifer, processes of anterior femora of the male, and on the head and thorax of the female.
Onthophagus.
Onthophagus rangifer, sexual differences of; variations in the horns of the male.
Ophidia, sexual differences of.
Ophidium.
Opossum, wide range of, in America.
Optic nerve, atrophy of the, caused by destruction of the eye.
Orang-Outan, Bischoff on the agreement of the brain of the, with that of man; adult age of the; ears of the; vermiform appendage of; hands of the; absence of mastoid processes in the; platforms built by the; alarmed at the sight of a turtle; using a stick as a lever; using missiles; using the leaves of the Pandanus as a night covering; direction of the hair on the arms of the; its aberrant characters; supposed evolution of the; voice of the; monogamous habits of the; male, beard of the.
Oranges, treatment of, by monkeys.
Orange-tip butterfly.
Orchestia Darwinii, dimorphism of males of.
Orchestia Tucuratinga, limbs of.
Ordeal, trial by.
Oreas canna, colours of.
Oreas Derbianus, colours of.
Organs, prehensile; utilised for new purposes.
Organic scale, von Baer's definition of progress in.
Orioles, nidification of.
Oriolus, species of, breeding in immature plumage.
Oriolus melanocephalus, coloration of the sexes in.
Ornaments, prevalence of similar; of male birds; fondness of savages for.
Ornamental characters, equal transmission of, to both sexes, in mammals; of monkeys.
Ornithoptera croesus.
Ornithorhynchus, reptilian tendency of; spur of the male.
Orocetes erythrogastra, young of.
Orrony, Grotto of.
Orsodacna atra, difference of colour in the sexes of.
Orsodacna ruficollis.
Orthoptera, metamorphosis of; stridulating apparatus of; colours of; rudimentary stridulating organs in female; stridulation of the, and Homoptera, discussed.
Ortygornis gularis, pugnacity of the male.
Oryctes, stridulation of; sexual differences in the stridulant organs of.
Oryx leucoryx, use of the horns of.
Osphranter rufus, sexual difference in the colour of.
Ostrich, African, sexes and incubation of the.
Ostriches, stripes of young.
Otaria jubata, mane of the male.
Otaria nigrescens, difference in the coloration of the sexes of.
Otis bengalensis, love-antics of the male.
Otis tarda, throat-pouch of the male; polygamous.