M.

_Macacus_, ears of, i. 23; convoluted body in the extremity of the tail of, i. 30; variability of the tail in species of, i. 150; whiskers of species of, ii. 283.

_Macacus cynomolgus_, superciliary ridge of, ii. 318; beard and whiskers of, becoming white with age, ii. 319.

_Macacus inornatus_, i. 151.

_Macacus lasiotus_, facial spots of, ii. 308.

_Macacus radiatus_, i. 192.

_Macacus rhesus_, sexual difference in the colour of, ii. 293, 310.

MACALISTER, Prof., on variations of the _palmaris accessorius_ muscle, i. 109; on muscular abnormalities in man, i. 128, 129; on the greater variability of the muscles in men than in women, i. 275.

MACAWS, Mr. Buxton’s observations on, i. 76; screams of, ii. 61.

MCCANN, J., on mental individuality, i. 63.

MCCLELLAND, J., on the Indian cyprinidæ, ii. 17.

MACCULLOCH, Col., on an Indian village without any female children, ii. 364.

MACCULLOCH, Dr., on tertian ague in a dog, i. 13.

MACGILLIVRAY, W., on the vocal organs of birds, i. 59; on the Egyptian goose, ii. 48; on the habits of woodpeckers, ii. 63; on the habits of the snipe, ii. 64; on the white-throat, ii. 69; on the moulting of the snipes, ii. 82; on the moulting of the anatidæ, ii. 85; on the finding of new mates by magpies, ii. 103; on the pairing of a blackbird and thrush, ii. 113; on pied ravens, ii. 126; on the guillemots, ii. 127; on the colours of the tits, ii. 174; on the immature plumage of birds, ii. 186 _et seqq._

_Machetes_, sexes and young of, ii. 216.

_Machetes pugnax_, numerical proportion of the sexes in, i. 306; supposed to be polygamous, i. 270; pugnacity of the male, ii. 41; double moult in, ii. 81.

MACKINTOSH, on the moral sense, i. 70.

MACLACHLAN, R., on _Apatania muliebris_ and _Boreus hyemalis_, i. 314; on the anal appendages of male insects, i. 342; on the pairing of dragon-flies, i. 347; on dragon-flies, i. 362, 363; on dimorphism in _Agrion_, i. 363; on the want of pugnacity in male dragon-flies, i. 364; on the ghost-moth in the Shetland Islands, i. 402.

MCLENNAN, Mr., on the origin of the belief in spiritual agencies, i. 66; on the prevalence of licentiousness among savages, i. 96, ii. 358; on infanticide, i. 134, ii. 363; on the primitive barbarism of civilised nations, i. 181; on traces of the custom of the forcible capture of wives, i. 182, ii. 365; on polyandry, ii. 365.

MCNEILL, Mr., on the use of the antlers of deer, ii. 252; on the Scotch deerhound, ii. 261; on the long hairs of the throat of the stag, ii. 268; on the bellowing of stags, ii. 274.

_Macrorhinus proboscideus_, structure of the nose of, ii. 278.

MAGPIE, power of speech of, i. 59; stealing bright objects, ii. 112; nuptial assemblies of, ii. 102; new mates found by, ii. 103; young of the, ii. 209; coloration of the, ii. 230.

MAGPIES, vocal organs of the, ii. 55.

MAILLARD, M., on the proportion of the sexes in a species of _Papilio_ from Bourbon, i. 310.

MAINE, Mr., on the absorption of one tribe by another, i. 159; on the want of a desire for improvement, i. 166.

MAKALOLO, perforation of the upper lip by the, ii. 341.

MALAR bone, abnormal division of, in man, i. 124.

MALAY, Archipelago, marriage-customs of the savages of the, ii. 373.

MALAYS, line of separation between the Papuans and the, i. 218; general beardlessness of the, ii. 321; staining of the teeth among, ii. 339; aversion of some, to hairs on the face, ii. 349.

MALAYS and Papuans, contrasted characters of, i. 216.

MALE animals, struggles of, for the possession of the females, i. 259, 260; eagerness of, in courtship, i. 272, 273; generally more modified than female, i. 272, 275; differ in the same way from females and young, i. 285.

MALE characters, developed in females, i. 280; transfer of, to female birds, ii. 193.

MALE, sedentary, of a hymenopterous parasite, i. 272.

MALEFACTORS, i. 172.

MALES, presence of rudimentary female organs in, i. 208.

MALES and females, comparative mortality of, while young, i. 264, 276; comparative numbers of, i. 261, 263.

MALHERBE, on the woodpeckers, ii. 174.

MALTHUS, T., on the rate of increase of population, i. 131, 132, 134.

MALURIDÆ, nidification of the, ii. 169.

_Malurus_, young of, ii. 216.

MAMMÆ, i. 254; rudimentary, in male mammals, i. 17, 30, 208, 209, 210; supernumerary, in women, i. 125; of male human subject, i. 130.

MAMMALIA, Prof. Owen’s classification of, i. 187; genealogy of the, i. 203.

MAMMALS, secondary sexual characters of, ii. 239; weapons of, ii. 241; recent and tertiary, comparison of cranial capacity of, i. 146; relative size of the sexes of, ii. 260; pursuit of female, by the males, i. 272; parallelism of, with birds in secondary sexual characters, ii. 297; voices of, used especially during the breeding season, ii. 331.

MAN, variability of, i. 108; erroneously regarded as more domesticated than other animals, i. 111; definitive origin of, i. 235; migrations of, i. 135; wide distribution of, i. 137; causes of the nakedness of, i. 149; supposed physical inferiority of, i. 156; numerical proportions of the sexes in, i. 264; a member of the Catarrhine group, i. 198; early progenitors of, i. 206; secondary sexual characters of, ii. 316; primeval condition of, ii. 367.

MANDANS, correlation of colour and texture of hair in the, i. 248.

MANDIBLE, left, enlarged in the male of _Taphroderes distortus_, i. 344.

MANDIBLES, use of the, in _Ammophila_, i. 342; large, of _Corydalis cornutus_, i. 342; large, of male _Lucanus elaphus_, i. 342.

MANDRILL, number of caudal vertebræ in the, i. 150; colours of the male, ii. 292, 296, 310.

MANTEGAZZA, Prof., on the ornaments of savages, ii. 338 _et seqq._; on the beardlessness of the New Zealanders, ii. 349; on the exaggeration of natural characters by man, ii. 351.

MANTELL, W., on the engrossment of pretty girls by the New Zealand chiefs, ii. 369.

_Mantis_, pugnacity of species of, i. 360.

MARCUS Aurelius, on the origin of the moral sense, i. 71; on the influence of habitual thoughts, i. 101.

_Mareca penelope_, ii. 114.

MARKS, retained throughout groups of birds, ii. 131.

MARRIAGE, influence of, upon morals, i. 96; restraints upon, among savages, i. 133; influence of, on mortality, i. 175; development of, ii. 361.

MARRIAGES, communal, ii. 358, 360; early, i. 174, 175.

MARSHALL, Mr., on the brain of a Bushwoman, i. 216.

MARSUPIALS, i. 202; possession of nipples by, i. 209; their origin from Monotremata, i. 213; uterus of, i. 122; development of the nictitating membrane in, i. 23; abdominal sacks of, i. 254; relative size of the sexes of, ii. 260; colours of, ii. 286.

MARSUPIUM, rudimentary, in male marsupials, i. 208.

MARTIN, W. C. L., on alarm manifested by an orang at the sight of a turtle, i. 43; on the hair in _Hylobates_, i. 194; on a female American deer, ii. 258; on the voice of _Hylobates agilis_, ii. 277; on _Semnopithecus nemæus_, ii. 312.

MARTIN, on the beards of the inhabitants of St. Kilda, ii. 321.

MARTINS deserting their young, i. 84.

MARTINS, C., on death caused by inflammation of the vermiform appendage, i. 28.

MASTOID processes in man and apes, i. 143.

MAUDSLEY, Dr., on the influence of the sense of smell in man, i. 24; on Laura Bridgman, i. 58; on the development of the vocal organs, i. 59.

MAYERS, W. F., on the domestication of the goldfish in China, ii. 17.

MAYHEW, E., on the affection between individuals of different sexes in the dog, ii. 270.

MAYNARD, C. J., on the sexes of _Chrysemys picta_, ii. 28.

MECKEL, on correlated variation of the muscles of the arm and leg, i. 130.

MEDICINES, effect produced by, the same in man and in monkeys, i. 12.

_Medusæ_, bright colours of some, i. 322.

MEGALITHIC structures, prevalence of, i. 233.

_Megalophrys montana_, sexual differences in, ii. 26, 27.

_Megapicus validus_, sexual difference of colour in, ii. 174.

_Megasoma_, large size of males of, i. 347.

MEIGS, Dr. A., on variation in the skulls of the natives of America, i. 108.

MEINECKE, on the numerical proportion of the sexes in butterflies, i. 309.

MELIPHAGIDÆ, Australian, nidification of, ii. 169.

_Melita_, secondary sexual characters of, i. 331.

_Meloë_, difference of colour in the sexes of a species of, i. 367.

MEMORY, manifestations of, in animals, i. 45.

MEMNON, young, i. 217.

MENTAL characters, difference of, in different races of men, i. 216.

MENTAL faculties, variation of, in the same species, i. 36, 110; diversity of, in the same race of men, i. 109; inheritance of, i. 110; similarity of the, in different races of man, i. 232; of birds, ii. 108.

MENTAL powers, difference of, in the two sexes in man, ii. 326.

_Menura Alberti_, ii. 102; song of, ii. 55.

_Menura superba_, ii. 101, 102; long tails of both sexes of, ii. 164.

MERGANSER, trachea of the male, ii. 60.

_Mergus cucullatus_, speculum of, i. 291.

_Mergus merganser_, young of, ii. 189.

_Merganser serrator_, male plumage of, ii. 85.

_Metallura_, splendid tail-feathers of, ii. 152.

_Methoca ichneumonides_, large male of, i. 347.

MEVES, M., on the drumming of the snipe, ii. 63.

MEXICANS, civilisation of the, not foreign, i. 183.

MEYER, on a convoluted body at the extremity of the tail in a _Macacus_ and a cat, i. 30.

MEYER, Dr. A., on the copulation of phryganidæ of distinct species, i. 342.

MIGRATIONS of man, effects of, i. 135.

MIGRATORY instinct of birds, i. 79; vanquishing the maternal, i. 83, 90.

MILL, J. S., on the origin of the moral sense, i. 71; on the “greatest happiness principle,” i. 97; on the difference of the mental powers in the sexes of man, ii. 328.

MILLIPEDES, i. 339.

MILNE-EDWARDS, H., on the use of the enlarged chela of the male _Gelasimus_, i. 331.

_Milvago leucurus_, sexes and young of, ii. 205.

MIMICKRY, i. 411.

_Mimus polyglottus_, ii. 109.

MIND, difference of, in man and the highest animals, i. 104; similarity of the, in different races, i. 232.

MINNOW, proportion of the sexes in the, i. 308, 309.

MINNOWS, spawning habits of, ii. 15.

MIRROR, larks attracted by, ii. 112.

MIVART, St. George, on the reduction of organs, i. 18; on the ears of the lemuroidea, i. 23; on variability of the muscles in lemuroidea, i. 128, 136; on the caudal vertebræ of monkeys, i. 150; on the classification of the primates, i. 196; on the orang and on man, i. 197; on differences in the lemuroidea, i. 198; on the crest of the male newt, ii. 24.

MOCKING-THRUSH, partial migration of, ii. 109; young of the, ii. 219.

MODIFICATIONS, unserviceable, i. 153.

MOLES, numerical proportion of the sexes in, i. 305; battles of male, ii. 239.

_Mollienesia petenensis_, sexual difference in, ii. 9.

MOLLUSCA, beautiful colours and shapes of, i. 326; absence of secondary sexual characters in the, i. 324.

MOLLUSCOIDA, i. 205, 324.

_Monacanthus scopas_ and _M. Peronii_, sexual differences in, ii. 12.

MONGOLIANS, perfection of the senses in, i. 119.

MONKEY, protecting his keeper from a baboon, i. 78, 87; bonnet-, i. 192; rhesus, sexual difference in colour of the, ii. 293, 310; moustache-, colours of the, ii. 291.

MONKEYS, liability of, to the same diseases as man, i. 11; male, recognition of women by, i. 13; revenge taken by, i. 40; maternal affection in, i. 40; variability of the faculty of attention in, i. 44; using stones and sticks, i. 51; imitative faculties of, i. 56; signal-cries of, i. 57; sentinels posted by, i. 74; diversity of the mental faculties in, i. 110; mutual kindnesses of, i. 75; hands of the, i. 139, 140; breaking hard fruits with stones, i. 140; basal caudal vertebræ of, imbedded in the body, i. 151; human characters of, i. 191; gradation of species of, i. 227; beards of, ii. 283; ornamental characters of, ii. 306; analogy of sexual differences of, with those of man, ii. 318; different degrees of difference in the sexes of, ii. 323; expression of emotions by, ii. 336; generally monogamous habits of, ii. 361; polygamous habits of some, ii. 362; naked surfaces of, ii. 376; American, manifestation of reason in, i. 47; American, direction of the hair on the arms of some, i. 192.

MONOGAMY, not primitive, i. 182.

MONOGENISTS, i. 228.

_Mononychus pseudacori_, stridulation of, i. 382.

MONOTREMATA, i. 202; development of the nictitating membrane in, i. 23; lactiferous glands of, i. 209; connecting mammals with reptiles, i. 213.

MONSTROSITIES, analogous, in man and lower animals, i. 113; caused by arrest of development, i. 121; correlation of, i. 130; transmission of, i. 224.

MONTAGU, G., on the habits of the black and red grouse, i. 269; on the pugnacity of the ruff, ii. 41; on the singing of birds, ii. 52; on the double moult of the male pintail, ii. 84.

MONTEIRO, Mr., on _Bucorax abyssinicus_, ii. 72.

MONTES DE OCA, M., on the pugnacity of male Humming-birds, ii. 40.

_Monticola cyanea_, ii. 172.

MONUMENTS, as traces of extinct tribes, i. 237.

MOOSE, battles of, ii. 240; horns of the, an incumbrance, ii. 259.

MORAL and instinctive impulses, alliance of, i. 88.

MORAL faculties, their influence on natural selection in man, i. 158.

MORAL rules, distinction between the higher and lower, i. 100.

MORAL sense, origin of the, i. 102; so-called, derived from the social instincts, i. 97, 98.

MORAL tendencies, inheritance of, i. 102.

MORALITY, supposed to be founded in selfishness, i. 97; test of, the general welfare of the community, i. 98; gradual rise of, i. 103; influence of a high standard of, i. 166.

MORGAN, L. H., on the Beaver, i. 37; on the reasoning powers of the Beaver, i. 46; on the forcible capture of wives, i. 182; on the castoreum of the beaver, ii. 279; marriage unknown in primeval times, ii. 359; on Polyandry, ii. 365.

MORRIS, F. O., on hawks feeding an orphan nestling, ii. 107.

MORTALITY, comparative, of females and males, i. 264, 276, 302.

MORTON, on the number of species of man, i. 226.

_Moschus moschiferus_, odoriferous organs of, ii. 280.

_Motacillæ_, Indian, young of, ii. 190.

MOTHS, i. 394; absence of mouth in some male, i. 254; apterous female, i. 255; male, prehensile use of the tarsi by, i. 256; male, attracted by females, i. 311; coloration of, i. 397; sexual differences of colour in, i. 398.

MOTMOT, racket-shaped feathers in the tail of a, ii. 73.

MOULT, double, ii. 181; double annual, in birds, ii. 80.

MOULTING of birds, ii. 214.

MOULTS, partial, ii. 83.

MOUSTACHE-MONKEY, colours of the, ii. 291, 311.

MOUSTACHES, in monkeys, i. 192.

MUD-TURTLE, long claws of the male, ii. 28.

MULATTOES, persistent fertility of, i. 221; immunity of, from yellow fever, i. 243.

MULE, sterility and strong vitality of the, i. 221.

MULES, rational, i. 48.

MÜLLER, Ferd., on the Mexicans and Peruvians, i. 183.

MÜLLER, Fritz, on astomatous males of _Tanais_, i. 255; on the disappearance of spots and stripes in adult mammals, ii. 305; on the proportions of the sexes in some Crustacea, i. 315; on secondary sexual characters in various Crustaceans, i. 328 _et seqq._; on the luminous larva of a beetle, i. 345; musical contest between male _Cicadæ_, i. 351; on the sexual maturity of young amphipod Crustacea, ii. 215.

MÜLLER, J., on the nictitating membrane and semilunar fold, i. 23.

MÜLLER, Max, on the origin of language, i. 56; struggle for life among the words, &c., of languages, i. 60.

MÜLLER, S., on the Banteng, ii. 290; on the colours of _Semnopithecus chrysomelas_, ii. 291.

MUNTJAC-DEER, weapons of the, ii. 257.

MURIE, J., on the reduction of organs, i. 18; on the ears of the Lemuroidea, i. 23; on variability of the muscles in the Lemuroidea, i. 128, 136; basal caudal vertebræ of _Macacus inornatus_ imbedded in the body, i. 151; on differences in the Lemuroidea, i. 198; on the throat-pouch of the male Bustard, ii. 58; on the mane of _Otaria jubata_, ii. 267; on the suborbital pits of Ruminants, ii. 280; on the colours of the sexes in _Otaria nigrescens_, ii. 287.

MURRAY, A., on the _Pediculi_ of different races of men, i. 219.

MURRAY, T. A., on the fertility of Australian women with white men, i. 220.

_Mus coninga_, i. 50.

_Mus minutus_, sexual difference in the colour of, ii. 286.

_Musca vomitoria_, i. 145.

_Muscicapa grisola_, ii. 170.

_Muscicapa luctuosa_, ii. 170.

_Muscicapa ruticilla_, breeding in immature plumage, ii. 214.

MUSCLE, ischio-pubic, i. 127.

MUSCLES, rudimentary, occurrence of, in man, i. 19; variability of the, i. 109; effects of use and disuse upon, i. 116; animal-like abnormalities of, in man, i. 127; correlated variation of, in the arm and leg, i. 130; variability of, in the hands and feet, i. 136; of the jaws, influence of, on the physiognomy of the Apes, i. 144; habitual spasms of, causing modifications of the facial bones, i. 147; of the early progenitors of man, i. 206; greater variability of the, in men than in women, i. 275.

MUSCULUS STERNALIS, Prof. Turner on the, i. 19.

MUSIC, i. 232; of birds, ii. 51; discordant, love of savages for, ii. 67; different appreciation of, by different peoples, ii. 333; origin of, ii. 333, 337; effects of, ii. 335.

MUSICAL cadences, perception of, by animals, ii. 333; powers of man, ii. 330 _et seqq._

MUSK-DEER, canine teeth of male, ii. 241, 256, 257; male, odoriferous organs of the, ii. 280; winter change of the, ii. 299.

MUSK-DUCK, Australian, ii. 38; large size of male, ii. 43; of Guiana, pugnacity of the male, ii. 43.

MUSK-OX, horns of, ii. 247.

MUSK-RAT, protective resemblance of the, to a clod of earth, ii. 298.

_Musophagæ_, colours and nidification of the, ii. 171; both sexes of, equally brilliant, ii. 177.

MUSSELS opened by monkeys, i. 140.

_Mustela_, winter change of two species of, ii. 298.

MUTILATIONS, healing of, i. 13.

_Mutilla europæa_, stridulation of, i. 366.

MUTILLIDÆ, absence of ocelli in female, i. 341.

_Mycetes caraya_, polygamous, i. 266; vocal organs of, ii. 277; beard of, ii. 283; sexual differences of colour in, ii. 290; voice of, ii. 332.

_Mycetes seniculus_, sexual differences of colour in, ii. 290.

MYRIAPODA, i. 339.

N.

NÄGELI, on the influence of natural selection on plants, i. 152; on the gradation of species of plants, i. 227.

NAILS, coloured yellow or purple in part of Africa, ii. 339.

NAPLES, greater proportion of female illegitimate children in, i. 301.

NARWHAL, tusks of the, ii. 242, 248.

NASAL cavities, large size of, in American aborigines, i. 119.

NASCENT organs, i. 18.

NATHUSIUS, H. von, on the improved breeds of pigs, i. 230; on the breeding of domestic animals, ii. 370.

NATURAL selection, its effects on the early progenitors of man, i. 136; influence of, on man, i. 151, 154; limitation of the principle, i. 152; influence of, on social animals, i. 155; Mr. Wallace on the limitation of, by the influence of the mental faculties in man, i. 158; influence of, in the progress of the United States, i. 179.

NATURAL and sexual selection contrasted, i. 278.

NAULETTE, jaw from, large size of the canines in, i. 126.

NEANDERTHAL skull, capacity of the, i. 146.

NECK, proportion of, in soldiers and sailors, i. 117.

_Necrophorus_, stridulation of, i. 378, 382.

_Nectarinia_, young of, ii. 190.

_Nectariniæ_, nidification of, ii. 169; moulting of the, ii. 83.

NEGRO, resemblance of a, to Europeans, in mental characters, i. 232.

NEGRO-WOMEN, their kindness to Mungo Park, i. 95.

NEGROES, character of, i. 216; lice of, i. 220; blackness of, i. 224, ii. 381; variability of, i. 225, 226; immunity of, from yellow fever, i. 243; difference of, from Americans, i. 247; disfigurements of the, ii. 296; colour of newborn children of, ii. 318; comparative beardlessness of, ii. 321; readily become musicians, ii. 334; appreciation of beauty of their women by, ii. 344, 346; idea of beauty among, ii. 350; compression of the nose by some, ii. 352.

NEOLITHIC period, 183.

_Neomorpha_, sexual difference of the beak in, ii. 39.

_Nephila_, i. 337.

NESTS, made by fishes, ii. 19; decoration of, by Humming-birds, ii. 112.

NEUMEISTER, on a change of colour in pigeons after several moultings, i. 294.

NEURATION, difference of, in the two sexes of some butterflies and hymenoptera, i. 345.

NEUROPTERA, i. 314, 361.

_Neurothemis_, dimorphism in, i. 363.

NEW ZEALAND, expectation by the natives of, of their extinction, 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.

NOCTUÆ, brightly-coloured beneath, i. 397.

NOCTUIDÆ, 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 Mutillidæ, 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.

_Œcanthus 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, i. 11; adult age of the, i. 13; ears of the, i. 21; vermiform appendage of, i. 27; platforms built by the, i. 36; alarmed at the sight of a turtle, i. 43; using a stick as a lever, i. 51; using missiles, i. 52; using the leaves of the _Pandanus_ as a night covering, i. 53; hands of the, i. 139; absence of mastoid processes in the, i. 143; direction of the hair on the arms of the, i. 192; its aberrant characters, i. 197; supposed evolution of the, i. 230; voice of the, ii. 276; monogamous habits of the, ii. 361; male, beard of the, ii. 284.

ORANGES, treatment of, by monkeys, i. 139.

ORANGE-TIP butterfly, i. 388, 393, 394.

_Orchestia Darwinii_, dimorphism of males of, i. 332.

_Orchestia Tucuratinga_, limbs of, i. 330, 331, 337.

ORDEAL, i. 68.

_Oreas canna_, colours of, ii. 288.

_Oreas derbyanus_, colours of, ii. 288, 299.

ORGANS, prehensile, i. 256; utilised for new purposes, ii. 335.

ORGANIC scale, von Baer’s definition of progress in, i. 211.

ORIOLES, nidification of, ii. 167.

_Oriolus_, species of, breeding in immature plumage, ii. 214, 215.

_Oriolus melanocephalus_, coloration of the sexes in, ii. 178.

ORNAMENTS, prevalence of similar, i. 233; fondness of savages for, ii. 338; of male birds, ii. 50.

ORNAMENTAL characters, equal transmission of, to both sexes, in mammals, ii. 297; of monkeys, ii. 306.

_Ornithoptera croesus_, i. 310.

_Ornithorhynchus_, i. 200; spur of the male, ii. 242; reptilian tendency of, i. 204.

_Orocetes erythrogastra_, young of, ii. 219.

ORRONY, Grotto of, i. 28.

_Orsodacna atra_, difference of colour in the sexes of, i. 368.

ORTHOPTERA, i. 352; metamorphosis of, i. 292; stridulating, auditory apparatus of, i. 353; colours of, i. 360; rudimentary stridulating organs in female, i. 359; stridulation of the, and Homoptera, discussed, i. 360.

_Ortygornis gularis_, pugnacity of the male, ii. 44.

_Oryctes_, stridulation of, i. 381; sexual differences in the stridulant organs of, i. 383.

_Oryx leucoryx_, use of the horns of, ii. 251, 263.

_Osphranter rufus_, sexual difference in the colour of, ii. 286.

OSTRICH, African, sexes and incubation of the, ii. 205.

OSTRICHES, stripes of young, ii. 184.

_Otaria jubata_, mane of the male, ii. 267.

_Otaria nigrescens_, difference in the coloration of the sexes of, ii. 287.

_Otis bengalensis_, love-antics of the male, ii. 68.

_Otis tarda_, polygamous, i. 269; throat-pouch of the male, ii. 58.

OUZEL, ring-, colours and nidification of the, ii. 179.

OUZEL, water-, colours and nidification of the, ii. 170.

_Ovibos moschatus_, horns of, ii. 247.

OVIPOSITOR of insects, i. 254.

_Ovis cycloceros_, mode of fighting of, ii. 249.

OVULE of man, i. 14.

OWEN, Prof., on the Corpora Wolffiana, i. 16; on the great toe in man, i. 16; on the nictitating membrane and semilunar fold, i. 23; on the development of the posterior molars in different races of man, i. 26; on the length of the cæcum in the Koala, i. 27; on the coccygeal vertebræ, i. 29; on rudimentary structures belonging to the reproductive system, i. 31; on abnormal conditions of the human uterus, i. 123; on the number of digits in the Ichthyopterygia, i. 125; on the canine teeth in man, i. 126; on the walking of the chimpanzee and orang, i. 139; on the mastoid processes in the higher apes, i. 143; on the hairiness of elephants in elevated districts, i. 149; on the caudal vertebræ of monkeys, i. 150; classification of mammalia, i. 187; on the hair in monkeys, i. 194; on the piscine affinities of the Ichthyosaurians, i. 204; on polygamy and monogamy among the antelopes, i. 267; on the horns of _Antilocapra americana_, i. 289; on the musky odour of crocodiles during the breeding season, ii. 29; on the scent-glands of snakes, ii. 30; on the Dugong, Cachalot and _Ornithorhynchus_, ii. 242; on the antlers of the red deer, ii. 252; on the dentition of the camelidæ, ii. 257; on the tusks of the Mammoth, ii. 258; on the horns of the Irish elk, ii. 259; on the voice in the giraffe, porcupine, and stag, ii. 274; on the laryngeal sac of the gorilla and orang, ii. 276; on the odoriferous glands of mammals, ii. 279, 280; on the effects of emasculation on the vocal organs of men, ii. 330; on the voice of _Hylobates agilis_, ii. 332; on American monogamous monkeys, ii. 362.

OWLS, white, new mates found by, ii. 105.

_Oxynotus_, difference of the females of two species of, ii. 193.

P.

PACHYDERMATA, i. 268.

PAGET, on the abnormal development of hairs in man, i. 25; on the thickness of the skin on the soles of the feet of infants, i. 118.

PAINTING, i. 232.

_Palæmon_, chelæ of a species of, i. 331.

_Palæornis_, sexual differences of colour in, ii. 231.

_Palæornis Javanicus_, colour of beak of, ii. 179.

_Palæornis rosa_, young of, ii. 188.

_Palamedea cornuta_, spurs on the wings, ii. 47.

PALEOLITHIC period, i. 183.

PALESTINE, habits of the chaffinch in, i. 307.

PALLAS, on the perfection of the senses in the Mongolians, i. 119; on the want of connexion between climate and the colour of the skin, i. 241; on the polygamous habits of _Antilope saiga_, i. 267; on the lighter colour of horses and cattle in winter in Siberia, i. 282; on the tusks of the musk-deer, ii. 256, 258; on the odoriferous glands of mammals, ii. 279; on the odoriferous glands of the musk-deer, ii. 280; on winter changes of colour in mammals, ii. 298; on the ideal of female beauty in North China, ii. 344.

_Palmaris accessorius_ muscle, variations of the, i. 109.

PAMPAS, horses of the, i. 236.

PANGENESIS, hypothesis of, i. 280, 284.

PANNICULUS carnosus, i. 19.

_Papilio_, sexual differences of colouring in species of, i. 389; proportion of the sexes in North American species of, i. 309; coloration of the wings in species of, i. 396.

_Papilio ascanius_, i. 389.

_Papilio Sesostris_ and _Childrenæ_, variability of, i. 402.

_Papilio Turnus_, i. 310.

_Papilionidæ_, variability in the, i. 402.

PAPUANS, line of separation between the, and the Malays, i. 218; beards of the, ii. 322; hair of, ii. 340.

PAPUANS and Malays, contrast in characters of, i. 216.

PARADISE, Birds of, ii. 100, 181; supposed by Lesson to be polygamous, i. 260; rattling of their quills by, ii. 61; racket-shaped feathers in, ii. 73; sexual differences in colour of, ii. 76; decomposed feathers in, ii. 74, 97; display of plumage by the male, ii. 88.

_Paradisea apoda_, barbless feathers in the tail of, ii. 74; plumage of, ii. 78; and _P. papuana_, divergence of the females of, ii. 192.

_Paradisea rubra_, ii. 75, 78.

PARAGUAY, Indians of, eradication of eyebrows and eyelashes by, ii. 348.

PARAKEET, Australian, variation in the colour of the thighs of a male, ii. 126.

PARALLELISM of development of species and languages, i. 59.

PARASITES on man and animals, i. 12; as evidence of specific identity or distinctness, i. 219; immunity from, correlated with colour, i. 242.

PARENTAL affection, partly a result of natural selection, i. 81.

PARENTS, age of, influence upon sex of offspring, i. 302.

PARINÆ, sexual difference of colour in, ii. 174.

PARK, Mungo, negro-women teaching their children to love the truth, i. 95; his treatment by the negro-women, i. 95, 326; on negro opinions of the appearance of white men, ii. 346.

PARROT, racket-shaped feathers in the tail of a, ii. 73; instance of benevolence in a, ii. 109.

PARROTS, imitative faculties of, i. 44; change of colour in, i. 152; living in triplets, ii. 106; affection of, ii. 108; colours of, ii. 223; sexual differences of colour in, ii. 231; colours and nidification of the, ii. 171, 174, 176; immature plumage of the, ii. 188; musical powers of, ii. 335.

PARTHENOGENESIS in the Tenthredinæ, i. 314; in Cynipidæ, i. 314; in Crustacea, i. 315.

PARTRIDGE, monogamous, i. 269; proportion of the sexes in the, i. 306; female, ii. 194.

“PARTRIDGE-DANCES,” ii. 68.

PARTRIDGES, living in triplets, ii. 106; spring coveys of male, ii. 107; distinguishing persons, ii. 110.

_Parus cæruleus_, ii. 174.

_Passer_, sexes and young of, ii. 212.

_Passer brachydactylus_, ii. 212.

_Passer domesticus_, ii. 170, 212.

_Passer montanus_, ii. 170, 212.

PATAGONIANS, self-sacrifice by, i. 88.

PATTERSON, Mr., on the _Agrionidæ_, i. 362.

PAULISTAS of Brazil, i. 225.

_Pavo cristatus_, i. 290; ii. 136.

_Pavo muticus_, i. 290, ii. 136; possession of spurs by the female, ii. 46, 162.

_Pavo nigripennis_, ii. 120.

PAYAGUAS Indians, thin legs and thick arms of the, i. 117.

PAYAN, Mr., on the proportion of the sexes in sheep, i. 305.

PEACOCK, polygamous, i. 269; sexual characters of, i. 290; pugnacity of the, ii. 46; rattling of the quills by, ii. 61; elongated tail-coverts of the, ii. 72, 97; love of display of the, ii. 135; 68, 87; ocellated spots of the, ii. 135; inconvenience of long tail of the, to the female, ii. 154, 164, 165; continued increase of beauty of the, ii. 216.

PEACOCK-BUTTERFLY, i. 392.

PEAFOWL, preference of females for a particular male, ii. 120; first advances made by the female, ii. 120.

_Pediculi_ of domestic animals and man, i. 219.

PEDIGREE of man, i. 213.

_Pedionomus torquatus_, sexes of, ii. 201.

PEEWIT, wing-tubercles of the male, ii. 48.

PELAGIC animals, transparency of, i. 323.

_Pelecanus erythrorhynchus_, horny crest on the beak of the male, during the breeding season, ii. 80.

_Pelecanus onocrotalus_, spring plumage of, ii. 85.

PELELÉ, ii. 341.

PELICAN, blind, fed by his companions, i. 77; young, guided by old birds, i. 77; pugnacity of the male, ii. 43.

PELICANS, fishing in concert, i. 75.

_Pelobius Hermanni_, stridulation of, i. 380, 382.

PELVIS, alteration of, to suit the erect attitude of man, i. 143; differences of the, in the sexes in man, ii. 317.

_Penelope nigra_, sound produced by the male, ii. 64.

PENNANT, on the battles of seals, ii. 240; on the bladder-nose seal, ii. 278.

_Penthe_, antennal cushions of the male, i. 343.

PERCH, brightness of male, during breeding season, ii. 13.

PEREGRINE Falcon, new mate found by, ii. 104.

PERIOD of variability, relation of, to sexual selection, i. 296.

PERIODICITY, vital, Dr. Laycock on, i. 12.

PERIODS, lunar, followed by functions in man and animals, i. 12, 212.

PERIODS of life, inheritance at corresponding, i. 280, 285.

_Perisoreus canadensis_, young of, ii. 209.

_Peritrichia_, difference of colour in the sexes of a species of, i. 367.

PERIWINKLE, i. 324.

_Pernis cristata_, ii. 126.

PERSEVERANCE, a characteristic of man, ii. 328.

PERSIANS, said to be improved by intermixture with Georgians and Circassians, ii. 357.

PERSONNAT, M., on _Bombyx Yamamai_, i. 310.

PERUVIANS, civilisation of the, not foreign, i. 183.

PETRELS, colours of, ii. 230.

_Petrocincla cyanea_, young of, ii. 219.

_Petronia_, ii. 212.

PFEIFFER, Ida, on Javanese ideas of beauty, ii. 347.

_Phacochœrus æthiopicus_, tusks and pads of, ii. 265.

PHALANGER, Vulpine, black varieties of the, ii. 294.

_Phalaropus fulicarius_, ii. 203.

_Phalaropus hyperboreus_, ii. 203.

_Phanæus_, i. 373.

_Phanæus carnifex_, variation of the horns of the male, i. 370.

_Phanæus faunus_, sexual differences of, i. 369.

_Phanæus lancifer_, i. 370.

_Phasgonura viridissima_, stridulation of, i. 354, 356.

_Phasianus Sœmmerringii_, ii. 157.

_Phasianus versicolor_, ii. 89.

_Phasianus Wallichii_, ii. 93, 196.

PHASMIDÆ, mimickry of leaves by the, i. 414.

PHEASANT, polygamous, i. 269; production of hybrids with the common fowl, ii. 122; and black grouse, hybrids of, ii. 113; immature plumage of the, ii. 188.

PHEASANT, Argus, ii. 72, 181; display of plumage by the male, ii. 91; ocellated spots of the, ii. 134, 141; gradation of characters in the, ii. 141.

PHEASANT, Blood-, ii. 46.

PHEASANT, Cheer, ii. 93, 195.

PHEASANT, Eared, i. 290, ii. 93, 195; sexes alike in the, ii. 178; length of the tail in the, ii. 166.

PHEASANT, Golden, display of plumage by the male, ii. 89; sex of young, ascertained by pulling out head-feathers, ii. 214; age of mature plumage in the, ii. 213.

PHEASANT, Kalij, drumming of the male, ii. 62.

PHEASANT, Reeve’s, length of the tail in, ii. 166.

PHEASANT, Silver, sexual coloration of the, ii. 228; triumphant male, deposed on account of spoiled plumage, ii. 120.

PHEASANT, Sœmmerring’s, ii. 156, 166.

PHEASANT, Tragopan, ii. 72; display of plumage by the male, ii. 91; markings of the sexes of the, ii. 134.

PHEASANTS, period of acquisition of male characters in the family of the, i. 290; proportion of sexes in chicks of, i. 306; length of the tail in, ii. 156, 164, 166.

_Philodromus_, i. 337.

PHILTERS, worn by women, ii. 344.

_Phoca grœnlandica_, sexual difference in the coloration of, ii. 287.

_Phœnicura ruticilla_, ii. 105.

PHOSPHORESCENCE of insects, i. 345.

PHRYGANIDÆ, copulation of distinct species of, i. 342.

_Phryniscus nigricans_, ii. 25.

PHYSICAL inferiority, supposed, of man, i. 156.

PICKERING, on the number of species of man, i. 226.

PICTON, J. A., on the soul of man, ii. 395.

_Picus auratus_, ii. 43.

PIERIDÆ, mimickry by female, i. 413.

_Pieris_, i. 393.

PIGEON, carrier, late development of the wattle in, i. 293; domestic, breeds and sub-breeds of, ii. 178; pouter, late development of the crop in, i. 293; female, deserting a weakened mate, i. 262.

PIGEONS, nestling, fed by the secretion of the crop of both parents, i. 210; changes of plumage in, i. 281; transmission of sexual peculiarities in, i. 283; changing colour after several moultings, i. 294; numerical proportion of the sexes in, i. 306; cooing of, ii. 60; variations in plumage of, ii. 74; display of plumage by male, ii. 96; local memory of, ii. 109; antipathy of female, to certain males, ii. 118; pairing of, ii. 118, 119; profligate male and female, ii. 119; wing-bars and tail-feathers of, ii. 131; supposititious breed of, ii. 155; pouter and carrier, peculiarities of predominant in males, ii. 158; nidification of, ii. 168; immature plumage of the, ii. 188; Australian, ii. 175; Belgian, with black-streaked males, i. 285, 293; ii. 157.

PIGS, origin of the improved breeds of, i. 230; numerical proportion of the sexes in, i. 305; stripes of young, ii. 184, 303; sexual preference shown by, ii. 273.

PIKE, American, brilliant colours of the male, during the breeding season, ii. 14.

PIKE, male, devoured by females, i. 308.

PIKE, L. O., on the psychical elements of religion, i. 68.

_Pimelia striata_, sounds produced by the female, i. 385.

PINTAIL Drake, plumage of, ii. 84; pairing with a wild duck, ii. 115.

PINTAIL Duck, pairing with a Wigeon, ii. 114.

PIPE-FISH, filamentous, ii. 18; marsupial receptacles of the male, ii. 21.

PIPITS, moulting of the, ii. 83.

_Pipra_, modified secondary wing-feathers of male, ii. 65.

_Pipra deliciosa_, ii. 65, 66.

_Pirates stridulus_, stridulation of, i. 350.

_Pithecia leucocephala_, sexual differences of colour in, ii. 290.

_Pithecia Satanas_, beard of, ii. 283, 284, 285; resemblance of, to a negro, ii. 381.

PITS, suborbital, of Ruminants, ii. 280.

PITTIDÆ, nidification of, ii. 167.

PLACENTATA, i. 202.

PLAGIOSTOMOUS fishes, ii. 1.

PLAIN-WANDERER, Australian, ii. 201.

_Planariæ_, bright colours of some, i. 322.

PLANTAIN-EATERS, colours and nidification of the, ii. 171; both sexes of, equally brilliant, ii. 177.

PLANTS, cultivated, more fertile than wild, i. 132; Nägeli, on natural selection in, i. 152; male flowers of, mature before the female, i. 260; phenomena of fertilisation in, i. 273; relation between number and size of seeds in, i. 317.

_Platalea_, ii. 60; change of plumage in, ii. 179.

_Platyblemnus_, i. 361.

_Platycercus_, young of, ii. 209.

_Platyphyllum concavum_, i. 352, 356.

PLATYRRHINE monkeys, i. 196.

PLATYSMA _myoides_, i. 19.

_Plecostomus_, head-tentacles of the male of a species of, ii. 10.

_Plecostomus barbatus_, peculiar beard of the male, ii. 10.

_Plectropterus gambensis_, spurred wings of, ii. 46.

_Ploceus_, ii. 54.

PLOVERS, wing-spurs of, ii. 48; double moult in, ii. 83.

PLUMAGE, changes of, inheritance of, by fowls, i. 281; tendency to analogous variation in, ii. 74; display of, by male birds, ii. 86, 96; changes of, in relation to season, ii. 180; immature, of birds, ii. 183, 187; colour of, in relation to protection, ii. 223.

PLUMES on the head in birds, difference of, in the sexes, ii. 164.

_Pneumora_, structure of, i. 357.

_Podica_, sexual difference in the colour of the irides of, ii. 128.

POEPPIG, on the contact of civilised and savage races, i. 239.

POISON, avoidance of, by animals, i. 49.

POISONOUS fruits and herbs avoided by animals, i. 36.

POISONS, immunity from, correlated with colour, i. 242.

POLISH fowls, origin of the crest in, i. 284.

POLLEN and van Dam, on the colours of _Lemur macaco_, ii. 290.

POLYANDRY, ii. 365; in certain cyprinidæ, i. 309; among the elateridæ, i. 313.

POLYDACTYLISM in man, i. 125.

POLYGAMY, influence of, upon sexual selection, i. 265; superinduced by domestication, i. 270; supposed increase of female births by, i. 303; in the stickleback, ii. 2.

POLYGENISTS, i. 228.

POLYNESIA, prevalence of infanticide in, ii. 364.

POLYNESIANS, aversion of, to hairs on the face, ii. 349; wide geographical range of, i. 112; difference of stature among the, i. 115; crosses of, i. 225; variability of, i. 225; heterogeneity of the, i. 241.

_Polyplectron_, display of plumage by the male, i. 89; number of spurs in, ii. 46; gradation of characters in, ii. 137; female of, ii. 194.

_Polyplectron chinquis_, ii. 90, 138, 139.

_Polyplectron Hardwickii_, ii. 138, 139.

_Polyplectron malaccense_, ii. 139, 140.

_Polyplectron Napoleonis_, ii. 138, 140.

POLYZOA, i. 324.

_Pontoporeia affinis_, i. 329.

PORCUPINE, mute, except in the rutting season, ii. 274.

PORES, excretory, numerical relation of, to the hairs in sheep, i. 248.

_Porpitæ_, bright colours of some, i. 322.

_Portax picta_, dorsal crest and throat-tuft of, ii. 282; sexual differences of colour in, ii. 287, 299.

_Portunus puber_, pugnacity of, i. 332.

_Potamochoerus penicillatus_, tusks and facial knobs of the, ii. 266.

POUCHET, G., on the ratio of instinct and intelligence, i. 37; on the instincts of ants, i. 187; on the caves of Abou-Simbel, i. 217; on the immunity of negroes from yellow fever, i. 243.

POUTER pigeon, late development of the large crop in, i. 293.

POWER, Dr., on the different colours of the sexes in a species of _Squilla_, i. 335.

POWYS, Mr., on the habits of the chaffinch in Corfu, i. 307.

PRE-EMINENCE of man, i. 137.

PREFERENCE for males by female birds, ii. 113, 122; shown by mammals, in pairing, ii. 268.

PREHENSILE organs, i. 256.

_Presbytis entellus_, fighting of the male, ii. 324.

PREYER, Dr., on supernumerary mammæ in women, i. 125.

PRICHARD, on the difference of stature among the Polynesians, i. 115; on the connection between the breadth of the skull in the Mongolians and the perfection of their senses, i. 119; on the capacity of British skulls of different ages, i. 146; on the flattened heads of the Colombian savages, ii. 340; on Siamese notions of beauty, ii. 345; on the beardlessness of the Siamese, ii. 349; on the deformation of the head among American tribes and the natives of Arakhan, ii. 352.

PRIMARY sexual organs, i. 254.

PRIMATES, i. 190; sexual differences of colour in, ii. 290.

PRIMOGENITURE, evils of, i. 170.

_Primula_, relation between number and size of seeds in, i. 317.

PRIONIDÆ, difference of the sexes in colour, i. 367.

_Proctotretus multimaculatus_, ii. 26, 37.

_Proctotretus tenuis_, sexual difference in the colour of, ii. 37.

PROFLIGACY, i. 173.

PROGENITORS, early, of man, i. 206.

PROGRESS, not the normal rule in human society, i. 166; elements of, i. 177.

PRONG-HORN, horns of, i. 289.

PROPORTIONS, difference of, in distinct races, i. 216.

PROTECTIVE colouring in butterflies, i. 392; in lizards, ii. 37; in birds, ii. 197, 223; in mammals, ii. 298, 299.

PROTECTIVE nature of the dull colouring of female Lepidoptera, i. 403, 405, 414.

PROTECTIVE resemblances in fishes, ii. 18.

PROTOZOA, absence of secondary sexual characters in, i. 321.

PRUNER-BEY, on the occurrence of the supra-condyloid foramen in the humerus of man, i. 29; on the colour of negro infants, ii. 318.

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

_Psocus_, proportions of the sexes in, i. 314.

PTARMIGAN, monogamous, i. 269; summer and winter plumage of the, ii. 81, 83; nuptial assemblages of, ii. 101; triple moult of the, ii. 181; protective coloration of, ii. 198.

PUFF-BIRDS, colours and nidification of the, ii. 171.

PUGNACITY of fine-plumaged male birds, ii. 93.

PUMAS, stripes of young, ii. 183.

PUPPIES learning from cats to clean their faces, i. 44.

_Pycnonotus hæmorrhous_, pugnacity of the male, ii. 41; display of under tail coverts by the male, ii. 96.

_Pyranga æstiva_, male aiding in incubation, ii. 167.

_Pyrodes_, difference of the sexes in colour, i. 367.

Q.

QUADRUMANA, hands of, i. 139; differences between man and the, i. 190; dependence of, on climate, i. 218; sexual differences of colour in, ii. 290; ornamental characters of, ii. 306; analogy of sexual differences of, with those of man, ii. 318; fighting of males for the females, ii. 324; monogamous habits of, ii. 361; beards of the, ii. 378.

QUAIN, R., on the variation of the muscles in man, i. 109.

QUATREFAGES, A. de, on the occurrence of a rudimentary tail in man, i. 29; on the moral sense as a distinction between man and animals, i. 70; on variability, i. 112; on the fertility of Australian women with white men, i. 221; on the Paulistas of Brazil, i. 225; on the evolution of the breeds of cattle, i. 230; on the Jews, i. 242; on the liability of negroes to tropical fevers after residence in a cold climate, i. 243; on the difference between field- and house-slaves, i. 246; on the influence of climate on colour, i. 246; on the Ainos, ii. 321; on the women of San-Giuliano, ii. 357.

QUECHUA Indians, i. 119; local variation of colour in the, i. 246; no grey hair among the, ii. 320; hairlessness of the, ii. 322; long hair of the, ii. 348.

_Querquedula acuta_, ii. 114.

_Quiscalus major_, proportions of the sexes of, in Florida and Honduras, i. 307.

R.

RABBIT, white tail of the, ii. 298.

RABBITS, danger-signals of, i. 74; domestic, elongation of the skull in, i. 147; modification of the skull in, by the lopping of the ear, i. 147; numerical proportion of the sexes in, i. 305.

RACES, distinctive characters of, i. 215; or species of man, i. 217; crossed, fertility or sterility of, i. 220; of man, variability of the, i. 225; of man, resemblance of, in mental characters, i. 232; formation of, i. 235; of man, extinction of, i. 236; effects of the crossing of, i. 240; of man, formation of the, i. 240; of man, children of the, ii. 318; beardless, aversion of, to hairs on the face, ii. 349.

RAFFLES, Sir S., on the Banteng, ii. 290.

RAFTS, use of, i. 137, 234.

RAGE, manifested by animals, i. 40.

_Raia batis_, teeth of, ii. 6.

_Raia clavata_, female spined on the back, ii. 2; sexual difference in the teeth of, ii. 6.

_Raia maculata_, teeth of, ii. 6.

RAILS, spur-winged, ii. 48.

RAM, mode of fighting of the, ii. 249; African, mane of an, ii. 284; fat-tailed, ii. 284.

RAMESES II., i. 217.

RAMSAY, Mr., on the Australian Musk-duck, ii. 38; on the Regent-bird, ii. 113; on the incubation of _Menura superba_, ii. 165.

_Rana esculenta_, vocal sacs of, ii. 28.

RAT, common, general dispersion of, a consequence of superior cunning, i. 50; supplantation of the native, in New Zealand, by the European rat, i. 240; common, said to be polygamous, i. 268; numerical proportion of the sexes in, i. 305.

RATS, enticed by essential oils, ii. 281.

RATIONALITY of birds, ii. 108.

RATTLE-SNAKES, difference of the sexes in the, ii. 29; said to use their rattles as a sexual call, ii. 30.

RAVEN, vocal organs of the, ii. 55; stealing bright objects, ii. 112; pied, of the Feroe Islands, ii. 120.

RAYS, prehensile organs of male, ii. 1.

RAZOR-BILL, young of the, ii. 217.

READE, Winwood, on the Guinea sheep, i. 289; non-development of horns in castrated male Guinea sheep, ii. 247; on the occurrence of a mane in an African ram, ii. 285; on the negroes’ appreciation of the beauty of their women, ii. 344; on the admiration of negroes for a black skin, ii. 346; on the idea of beauty among negroes, ii. 350; on the Jollofs, ii. 357; on the marriage-customs of the negroes, ii. 374.

REASON, in animals, i. 46.

REDSTART, American, breeding in immature plumage, ii. 214.

REDSTARTS, new mates found by, ii. 105.

REDUVIDÆ, stridulation of, i. 350.

REED-BUNTING, head-feathers of the male, ii. 95; attacked by a bullfinch, ii. 111.

REEFS, fishes frequenting, ii. 17.

REGENERATION, partial, of lost parts in man, i. 13.

REGENT-BIRD, ii. 112.

REINDEER, antlers of, with numerous points, ii. 252; sexual preferences shown by, ii. 273; horns of the, i. 288; winter change of the, ii. 299; battles of, ii. 240; horns of the female, ii. 243.

RELATIONSHIP, terms of, ii. 360.

RELIGION, deficiency of, among certain races, i. 65; psychical elements of, i. 68.

REMORSE, i. 91; deficiency of, among savages, i. 164.

RENGGER, on the diseases of _Cebus Azaræ_, i. 11; on maternal affection in a _Cebus_, i. 40; revenge taken by monkeys, i. 40; on the reasoning powers of American monkeys, i. 47; on the use of stones by monkeys for cracking hard nuts, i. 51; on the sounds uttered by _Cebus Azaræ_, i. 54; on the signal-cries of monkeys, i. 57; on the diversity of the mental faculties of monkeys, i. 110; on the Payaguas Indians, i. 117; on the inferiority of Europeans to savages in their senses, i. 118; on the polygamous habits of _Mycetes caraya_, i. 266; on the voice of the howling monkeys, ii. 277; on the odour of _Cervus campestris_, ii. 279; on the beards of _Mycetes caraya_ and _Pithecia Satanas_, ii. 283; on the colours of _Felis mitis_, ii. 287; on the colours of _Cervus paludosus_, ii. 290; on sexual differences of colour in _Mycetes_, ii. 291; on the colour of the infant Guaranys, ii. 318; on the early maturity of the female of _Cebus azaræ_, ii. 318; on the beards of the Guaranys, ii. 322, 323; on the emotional notes employed by monkeys, ii. 336; on American polygamous monkeys, ii. 362.

REPRESENTATIVE species, of birds, ii. 190, 191.

REPRODUCTION, unity of phenomena of, throughout the mammalia, i. 13; period of, in birds, ii. 214.

REPRODUCTIVE system, rudimentary structures in the, i. 30; accessory parts of, i. 207.

REPTILES, ii. 28.

REPTILES and birds, alliance of, i. 213.

RESEMBLANCES, small, between man and the apes, i. 191.

RETRIEVERS, exercise of reasoning faculties by, i. 48.

REVENGE, manifested by animals, i. 40.

REVERSION, i. 122; perhaps the cause of some bad dispositions, i. 173.

_Rhagium_, difference of colour in the sexes of a species of, i. 367.

_Ramphastos carinatus_, ii. 227.

RHINOCEROS, nakedness of, i. 148; horns of, ii. 247; horns of, used defensively, ii. 263; attacking white or grey horses, ii. 295.

_Rhynchæa_, sexes and young of, ii. 202.

_Rhynchæa australis_, ii. 203.

_Rhynchæa bengalensis_, ii. 203.

_Rhynchæa capensis_, ii. 202.

RHYTHM, perception of, by animals, ii. 333.

RICHARD, M., on rudimentary muscles in man, i. 19.

RICHARDSON, Sir J., on the pairing of _Tetrao umbellus_, ii. 49; on _Tetrao urophasianus_, ii. 58; on the drumming of grouse, ii. 63; on the dances of _Tetrao phasianellus_, ii. 69; on assemblages of grouse, ii. 101; on the battles of male deer, ii. 240; on the reindeer, ii. 244; on the horns of the musk-ox, ii. 247; on antlers of the reindeer with numerous points, ii. 252; on the moose, ii. 259.

RICHARDSON, on the Scotch deerhound, ii. 261.

RICHTER, Jean Paul, on imagination, i. 45.

RIEDEL, on profligate female pigeons, ii. 119.

RING-OUZEL, colours and nidification of the, ii. 170.

RIPA, Father, on the difficulty of distinguishing the races of the Chinese, i. 215.

RIVALRY, in singing, between male birds, ii. 53.

RIVER-HOG, African, tusks and knobs of the, ii. 266.

RIVERS, analogy of, to islands, i. 204.

ROACH, brightness of male during breeding-season, ii. 13.

ROBBERY, of strangers, considered honourable, i. 94.

ROBERTSON, Mr., remarks on the development of the horns in the roebuck and red-deer, i. 288.

ROBIN, pugnacity of the male, ii. 40; autumn song of the, ii. 54; female, singing of the, ii. 54; attacking other birds with red in their plumage, ii. 111; young of the, ii. 208.

ROBINET, on the difference of size of the male and female cocoons of the silk-moth, i. 346.

RODENTS, uterus in the, i. 123; absence of secondary sexual characters in, i. 268; sexual differences in the colours of, ii. 286.

ROE, winter change of the, ii. 299.

ROLLE, F., on the origin of man, i. 4; on a change in German families settled in Georgia, i. 246.

ROLLER, ii. 56.

ROMANS, ancient, gladiatorial exhibitions of the, i. 101.

ROOK, voice of the, ii. 61.

RÖSSLER, Dr., on the resemblance of the lower surface of butterflies to the bark of trees, i. 392.

ROSTRUM, sexual difference in the length of, in some weevils, i. 255.

RUDIMENTARY organs, i. 17; origin of, i. 32.

RUDIMENTS, presence of, in languages, i. 60.

RUDOLPH, on the want of connexion between climate and the colour of the skin, i. 241.

RUFF, supposed to be polygamous, i. 270; proportion of the sexes in the, i. 306; pugnacity of the, ii. 41, 48; double moult in, ii. 81, 84; duration of dances of, ii. 100; attraction of the, to bright objects, ii. 111.

RUMINANTS, male, disappearance of canine teeth in, i. 144, ii. 325; generally polygamous, i. 266; analogy of Lamellicorn beetles to, i. 373; suborbital pits of, ii. 280; sexual differences of colour in, ii. 287.

_Rupicola crocea_, display of plumage by the male, ii. 87.

RÜPPELL, on canine teeth in deer and antelopes, ii. 258.

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

_Ruticilla_, ii. 180.

RÜTIMEYER, Prof., on the physiognomy of the apes, i. 149; on the sexual differences of monkeys, ii. 323.

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

S.

SACHS, Prof., on the behaviour of the male and female elements in fertilisation, i. 274.

SACRIFICES, Human, i. 182.

SAGITTAL crest in male apes and Australians, ii. 319.

SAHARA, birds of the, ii. 172; animal inhabitants of the, ii. 224.

SAILORS, growth of, delayed by conditions of life, i. 114; long-sighted, i. 118.

SAILORS and soldiers, difference in the proportions of, i. 116.

ST. JOHN, Mr., on the attachment of mated birds, ii. 108.

ST. KILDA, beards of the inhabitants of, ii. 321.

_Salmo eriox_, and _S. umbla_, colouring of the male, during the breeding season, ii. 14.

_Salmo lycaodon_, ii. 4.

_Salmo salar_, ii. 4.

SALMON, leaping out of fresh water, i. 83; male, ready to breed before the female, i. 260; proportion of the sexes in, i. 308; male, pugnacity of the, ii. 3; male, characters of, during the breeding season, ii. 3, 14; spawning of the, ii. 19; breeding of immature male, ii. 215.

SALVIN, O., on the Humming-birds, i. 269, ii. 168; on the numerical proportion of the sexes in Humming-birds, i. 307, ii. 221; on _Chamæpetes_ and _Penelope_, ii. 64; on _Selasphorus platycercus_, ii. 65; on _Pipra deliciosa_, ii. 66; on _Chasmorhynchus_, ii. 79.

SAMOA Islands, beardlessness of the natives of, ii. 322, 349.

SAND-SKIPPER, i. 334.

SANDWICH Islands, variation in the skulls of the natives of the, i. 108; superiority of the nobles in the, ii. 356.

SANDWICH Islanders, lice of, i. 219.

SAN-GIULIANO, women of, ii. 357.

SANTALI, recent rapid increase of the, i. 133; Mr. Hunter on the, i. 241.

_Saphirina_, characters of the males of, i. 335.

_Sarkidiornis melanonotus_, characters of the young, ii. 185.

SARS, O., on _Pontoporeia offinis_, i. 329.

_Saturnia carpini_, attraction of males by the female, i. 311.

_Saturnia Io_, difference of coloration in the sexes of, i. 398.

_Saturniidæ_, coloration of the, i. 396, 398.

SAVAGE, Dr., on the fighting of the male gorillas, ii. 324; on the habits of the gorilla, ii. 363.

SAVAGE and Wyman, on the polygamous habits of the gorilla, i. 266.

SAVAGES, imitative faculties of, i. 57, 161; causes of low morality of, i. 97; uniformity of, exaggerated, i. 111; long-sighted, i. 118; rate of increase among, usually small, i. 132; retention of the prehensile power of the feet by, i. 142; tribes of, supplanting one another, i. 160; improvements in the arts among, i. 182; arts of, i. 234; fondness of, for rough music, ii. 67; attention paid by, to personal appearance, ii. 338; relation of the sexes among, ii. 363.

SAW-FLY, pugnacity of a male, i. 364.

SAW-FLIES, proportions of the sexes in, i. 314.

_Saxicola rubicola_, young of, ii. 220.

SCALP, motion of the, i. 20.

SCENT-GLANDS in snakes, ii. 30.

SCHAAFFHAUSEN, Prof., on the development of the posterior molars in different races of man, i. 26; on the jaw from La Naulette, i. 126; on the correlation between muscularity and prominent supra-orbital ridges, i. 130; on the mastoid processes of man, i. 143; on modifications of the cranial bones, i. 147; on human sacrifices, i. 182; on the probable speedy extermination of the anthropomorphous apes, i. 201; on the ancient inhabitants of Europe, i. 237; on the effects of use and disuse of parts, i. 247; on the superciliary ridge in man, ii. 316; on the absence of race-differences in the infant skull in man, ii. 318; on ugliness, ii. 354.

SCHAUM, H., on the elytra of _Dytiscus_ and _Hydroporus_, i. 343.

SCHELVER, on dragon-flies, i. 363.

SCHIODTE, on the stridulation of _Heterocerus_, i. 379.

SCHLEGEL, F. von, on the complexity of the languages of uncivilised peoples, i. 61.

SCHLEGEL, Prof., on _Tanysiptera_, ii. 190.

SCHLEICHER, Prof., on the origin of language, i. 56.

SCHLEIDEN, Prof., on the rattle-snake, ii. 30.

SCHOMBURGK, Sir R., on the pugnacity of the male musk-duck of Guiana, ii. 43; on the courtship of _Rupicola crocea_, ii. 87.

SCHOOLCRAFT, Mr., on the difficulty of fashioning stone implements, i. 138.

SCLATER, P. L., on modified secondary wing-feathers in the males of _Pipra_, ii. 65; on elongated feathers in nightjars, ii. 73; on the species of _Chasmorhynchus_, ii. 79; on the plumage of _Pelecanus onocrotalus_, ii. 85; on the plantain-eaters, ii. 177; on the sexes and young of _Tadorna variegata_, ii. 206; on the colours of _Lemur macaco_, ii. 290; on the stripes in asses, ii. 305.

SCOLECIDA, absence of secondary sexual characters in, i. 321.

_Scolopax frenata_, tail-feathers of, ii. 64.

_Scolopax gallinago_, drumming of, ii. 63.

_Scolopax javensis_, tail-feathers of, ii. 64.

_Scolopax major_, assemblies of, ii. 101.

_Scolopax Wilsonii_, sound produced by, ii. 64.

_Scolytus_, stridulation of, i. 379.

SCOTER-DUCK, black, sexual difference in coloration of the, ii. 226; bright beak of male, ii. 227.

SCOTT, J., on the colour of the beard in man, ii. 319.

SCROPE, on the pugnacity of the male salmon, ii. 3; on the battles of stags, ii. 240.

SCUDDER, S. H., imitation of the stridulation of the Orthoptera, i. 353; on the stridulation of the _Acridiidæ_, i. 356; on a Devonian insect, i. 360; on stridulation, ii. 331.

SCULPTURE, expression of the ideal of beauty by, ii. 350.

SEA-ANEMONIES, bright colours of, i. 322.

SEA-BEAR, polygamous, i. 268.

SEA-ELEPHANT, male, structure of the nose of the, ii. 278; polygamous, i. 268.

SEA-LION, polygamous, i. 268.

SEAL, bladder-nose, ii. 278.

SEALS, their sentinels generally females, i. 74; evidence furnished by, on classification, i. 190; sexual differences in the coloration of, ii. 287; appreciation of music by, ii. 333; battles of male, ii. 240; canine teeth of male, ii. 241; polygamous habits of, i. 268; pairing of, ii. 269; sexual peculiarities of, ii. 277.

SEA-SCORPION, sexual differences in, ii. 9.

SEASON, changes of colour in birds, in accordance with the, ii. 80; changes of plumage of birds in relation to, ii. 180.

SEASONS, inheritance at corresponding, i. 282.

SEBITUANI, ii. 340.

SEBRIGHT Bantam, i. 294.

SECONDARY sexual characters, i. 253; relations of polygamy to, i. 266; gradation of, in birds, ii. 135; transmitted through both sexes, i. 279.

SEDGWICK, W., on hereditary tendency to produce twins, i. 133.

SEEMANN, Dr., on the different appreciation of music by different peoples, ii. 334; on the effects of music, ii. 335.

_Selasphorus platycercus_, acuminate first primary of the male, ii. 65.

SELBY, P. J., on the habits of the black and red grouse, i. 269.

SELECTION, double, i. 276.

SELECTION of male by female birds, ii. 99, 122.

SELECTION, methodical, of Prussian grenadiers, i. 112.

SELECTION, sexual, influence of, on the colouring of Lepidoptera, i. 403; explanation of, i. 256, 260, 271.

SELECTION, sexual and natural, contrasted, i. 278.

SELF-COMMAND, habit of, inherited, i. 92; estimation of, i. 95.

SELF-CONSCIOUSNESS, i. 62.

SELF-PRESERVATION, instinct of, i. 89.

SELF-SACRIFICE, by savages, i. 88; estimation of, i. 95.

SEMILUNAR fold, i. 23.

_Semnopithecus_, i. 197; long hair on the heads of species of, i. 192; ii. 380.

_Semnopithecus chrysomelas_, sexual differences of colour in ii. 291.

_Semnopithecus comatus_, ornamental hair on the head of, ii. 307.

_Semnopithecus frontatus_, beard, &c., of, ii. 308.

_Semnopithecus nasica_, nose of, i. 192.

_Semnopithecus nemæus_, colouring of, ii. 310.

_Semnopithecus rubicundus_, ornamental hair on the head of, ii. 306.

SENSES, inferiority of Europeans to savages in the, i. 118.

SENTINELS, i. 74, 82.

SERPENTS, instinctively dreaded by apes and monkeys, i. 37, 42.

_Serranus_, hermaphroditism in, i. 208.

SEX, inheritance limited by, i. 282.

SEXES, relative proportions of, in man, i. 300, ii. 320; probable relation of the, in primeval man, ii. 362.

SEXUAL characters, secondary, i. 253; relations of polygamy to, i. 266; transmitted through both sexes, i. 279; gradation of, in birds, ii. 135.

SEXUAL and natural selection, contrasted, i. 278.

SEXUAL characters, effects of the loss of, i. 284; limitation of, i. 284.

SEXUAL differences in man, i. 14.

SEXUAL selection, explanation of, i. 256, 260, 271; influence of, on the colouring of Lepidoptera, i. 403;

## action of, in mankind, ii. 368.

SEXUAL similarity, i. 277.

SHARKS, prehensile organs of male, ii. 1.

SHARPE, R. B., on _Tanysiptera sylvia_, ii. 165; on _Ceryle_, ii. 173; on the young male of _Dacelo Gaudichaudi_, ii. 188.

SHAW, Mr., on the pugnacity of the male salmon, ii. 3.

SHAW, J., on the decorations of birds, ii. 71.

SHEEP, danger-signals of, i. 74; sexual differences in the horns of, i. 283; horns of, i. 289, ii. 246, 259; domestic, sexual differences of, late developed, i. 293; numerical proportion of the sexes in, i. 304; mode of fighting of, ii. 249; arched foreheads of some, ii. 284.

SHEEP, Merino, loss of horns in females of, i. 284; horns of, i. 289.

SHELLS, difference in form of, in male and female Gasteropoda, i. 324; beautiful colours and shapes of, i. 326.

SHIELD-DRAKE, pairing with a common duck, ii. 114; New Zealand, sexes and young of, ii. 206.

SHOOTER, J., on the Kafirs, ii. 347; on the marriage-customs of the Kafirs, ii. 373.

SHREW-MICE, odour of, ii. 279.

SHRIKE, Drongo, ii. 179.

SHRIKES, characters of young, ii. 185.

SHUCKARD, W. E., on sexual differences in the wings of Hymenoptera, i. 435.

SHYNESS of adorned male birds, ii. 97.

_Siagonium_, proportions of the sexes in, i. 314; dimorphism in males of, i. 374.

SIAM, proportion of male and female births in, i. 303.

SIAMESE, general beardlessness of the, ii. 321; notions of beauty of the, ii. 345; hairy family of, ii. 378.

SIEBOLD, C. T. von, on the auditory apparatus of the stridulant orthoptera, i. 353.

SIGHT, inheritance of long and short, i. 118.

SIGNAL-CRIES of monkeys, i. 57.

SILK-MOTH, difference of size of the male and female cocoons of the, i. 346; pairing of the, i. 401; male, fertilising two or three females, i. 406; proportion of the sexes in, i. 309, 311; Ailanthus, Prof. Canestrini, on the destruction of its larvæ by wasps, i. 311.

SIMIADÆ, i. 195; their origin and divisions, i. 213.

SIMILARITY, sexual, i. 277.

SINGING of the Cicadæ and Fulgoridæ, i. 351; of tree-frogs, ii. 27; of birds, object of the, ii. 52.

SIRENIA, nakedness of, i. 148.

_Sirex juvencus_, i. 365.

SIRICIDÆ, difference of the sexes in, i. 365.

SISKIN, ii. 85; pairing with a canary, ii. 115.

_Sitana_, throat-pouch of the males of, ii. 33, 36.

SIZE, relative, of the sexes of insects, i. 345.

SKIN, movement of the, i. 19; nakedness of, in man, i. 148; colour of the, i. 241.

SKIN and hair, correlation of colour of, i. 248.

SKULL, variation of, in man, i. 108; cubic contents of, no absolute test of intellect, i. 145; Neanderthal, capacity of the, i. 146; causes of modification of the, i. 147; difference of, in form and capacity, in different races of men, i. 216; variability of the shape of the, i. 226; differences of, in the sexes in man, ii. 317; artificial modifications of the shape of, ii. 340.

SKUNK, odour emitted by the, ii. 279.

SLAVERY, prevalence of, i. 94; of women, ii. 366.

SLAVES, difference between those of field and house, i. 246.

SMELL, sense of, in man and animals, i. 23.

SMITH, Adam, on the basis of sympathy, i. 82.

SMITH, Sir A., on the recognition of women by male _Cynocephali_, i. 13; on an instance of memory in a baboon, i. 45; on the retention of their colour by the Dutch in South Africa, i. 242; on the polygamy of the South African antelopes, i. 267; on the proportion of the sexes in _Kobus ellipsiprymnus_, i. 305; on _Bucephalus capensis_, ii. 29; on South African lizards, ii. 37; on fighting gnus, ii. 240; on the horns of rhinoceroses, ii. 248; on the fighting of lions, ii. 266; on the colours of the Cape Eland, ii. 288; on the colours of the gnu, ii. 289; on Hottentot notions of beauty, ii. 345.

SMITH, F., on the Cynipidæ and Tenthredinidæ, i. 314; on the relative size of the sexes of Aculeate Hymenoptera, i. 347; on the difference between the sexes of ants and bees, i. 365; on the stridulation of _Trox sabulosus_, i. 380; on the stridulation of _Mononychus pseudacori_, i. 382.

_Smynthurus luteus_, courtship of, i. 348.

SNAKES, sexual differences of, ii. 29; male, ardency of, ii. 30.

“SNARLING MUSCLES,” i. 127.

SNIPE, drumming of the, ii. 63; coloration of the, ii. 226.

SNIPE, painted, sexes and young of, ii. 202.

SNIPE, solitary, assemblies of, ii. 101.

SNIPES, arrival of male before the female, i. 260; pugnacity of male, ii. 43; double moult in, ii. 80.

SNOW-GOOSE, whiteness of the, ii. 228.

SOCIAL animals, affection of, for each other, i. 76; defence of, by the males, i. 83.

SOCIABILITY, the sense of duty connected with, i. 71; impulse to, in animals, i. 79, 80; manifestations of, in man, i. 84; instinct of, in animals, i. 86.

SOCIALITY, probable, of primeval men, i. 155; influence of, on the development of the intellectual faculties, i. 160; origin of, in man, i. 161.

SOLDIERS, American, measurements of, i. 114.

SOLDIERS and sailors, difference in the proportions of, i. 116.

_Solenostoma_, bright colours and marsupial sack of the females of, ii. 22.

SONG of male birds appreciated by their females, i. 63; want of, in brilliant plumaged birds, ii. 94; of birds, ii. 163.

_Sorex_, odour of, ii. 279.

SOUNDS admired alike by man and animals, i. 64; produced by fishes, ii. 23; produced by male frogs and toads, ii. 27; instrumentally produced by birds, ii. 63 _et seqq._

SPAIN, decadence of, i. 178.

_Sparassus smaragdulus_, difference of colour in the sexes of, i. 337, 338.

SPARROW, pugnacity of the male, ii. 40; acquisition of the Linnet’s song by a, ii. 55; coloration of the, ii. 198; immature plumage of the, ii. 188.

SPARROW, white-crowned, young of the, ii. 217.

SPARROWS, house- and tree-, ii. 170.

SPARROWS, new mates found by, ii. 105.

SPARROWS, sexes and young of, ii. 212; learning to sing, ii. 334.

_Spathura Underwoodi_, ii. 77.

SPAWNING of fishes, ii. 15, 19.

SPEAR, origin of the, i. 234.

SPECIES, causes of the advancement of, i. 172; distinctive characters of, i. 214; or races of man, i. 217; sterility and fertility of, when crossed, i. 122; supposed, of man, i. 226; gradation of, i. 227; difficulty of defining, i. 228; representative, of birds, ii. 190, 191; of birds, comparative differences between the sexes of distinct, ii. 192.

SPECTRE-INSECTS, mimickry of leaves by, i. 414.

_Spectrum femoratum_, difference of colour in the sexes of, i. 361.

SPEECH, connection between the brain and the faculty of, i. 58.

“SPEL” of the black-cock, ii. 60.

SPENCER, Herbert, on the dawn of intelligence, i. 37; on the origin of the belief in spiritual agencies, i. 66; on the origin of the moral sense, i. 101; on the influence of food on the size of the jaws, i. 118; on the ratio between individuation and genesis, i. 318; on music, ii. 336.

SPERM-WHALES, battles of male, ii. 240.

SPHINGIDÆ, coloration of the, i. 396.

SPHINX, Humming-bird, i. 399.

_Sphinx_, Mr. Bates on the caterpillar of a, i. 416.

SPIDERS, i. 337; male, more active than female, i. 272; proportion of the sexes in, i. 314; male, small size of, i. 338.

_Spilosoma menthrasti_, rejected by turkeys, i. 398.

SPINE, alteration of, to suit the erect attitude of man, i. 143.

SPIRITS, fondness of monkeys for, i. 12.

SPIRITUAL agencies, belief in, almost universal, i. 65.

SPOONBILL, ii. 60; Chinese, change of plumage in, ii. 179.

SPOTS, retained throughout groups of birds, ii. 131; disappearance of, in adult mammals, ii. 303.

SPRENGEL, C. K., on the sexuality of plants, i. 260.

SPRING-BOC, horns of the, ii. 251.

SPROAT, Mr., on the extinction of savages in Vancouver Island, i. 239; on the eradication of facial hair by the natives of Vancouver Island, ii. 348; on the eradication of the beard by the Indians of Vancouver Island, ii. 380.

SPURS, occurrence of, in female fowls, i. 280, 284; development of, in various species of Phasianidæ, i. 290; of Gallinaceous birds, ii. 44, 46; development of, in female Gallinaceæ, ii. 162.

_Squilla_, different colours of the sexes of a species of, i. 335.

SQUIRRELS, battles of male, ii. 239; African, sexual differences in the colouring of, ii. 286; black, ii. 294.

STAG, long hairs of the throat of, ii. 268; horns of the, i. 279, 282; battles of, ii. 240; horns of the, with numerous branches, ii. 252; bellowing of the, ii. 274; crest of the, ii. 282.

STAG-BEETLE, large size of male, i. 347; weapons of the male, i. 375; numerical proportion of sexes of, i. 313.

STAINTON, H. T., on the numerical proportion of the sexes in the smaller moths, i. 310; habits of _Elachista rufocinerea_, i. 311; on the coloration of moths, i. 397; on the rejection of _Spilosoma menthrasti_, by turkeys, i. 398; on the sexes of _Agrotis exclamationis_, i. 399.

STALLION, mane of the, ii. 268.

STALLIONS, two, attacking a third, i. 75; fighting, ii. 241; small canine teeth of, ii. 258.

STANSBURY, Capt., observations on pelicans, i. 77.

STAPHYLINIDÆ, hornlike processes in male, i. 374.

STARFISHES, bright colours of some, i. 322.

STARK, Dr., on the death-rate in towns and rural districts, i. 175; on the influence of marriage on mortality, i. 176; on the higher mortality of males in Scotland, i. 302.

STARLING, American field, pugnacity of male, ii. 51.

STARLING, red-winged, selection of a mate by the female, ii. 116.

STARLINGS, three, frequenting the same nest, i. 269, ii. 106; new mates found by, ii. 105.

STATUES, Greek, Egyptian, Assyrian, &c., contrasted, ii. 350.

STATURE, dependence of, upon local influences, i. 114.

STAUDINGER, Dr., his list of Lepidoptera, i. 312; on breeding Lepidoptera, i. 311.

STAUNTON, Sir G., hatred of indecency a modern virtue, i. 96.

STEALING of bright objects by birds, ii. 112.

STEBBING, T. R., on the nakedness of the human body, ii. 375.

_Stemmatopus_, ii. 278.

_Stenobothrus pratorum_, stridulating organs of, i. 357.

STERILITY, general, of sole daughters, i. 170; when crossed, a distinctive character of species, i. 214.

_Sterna_, seasonal change of plumage in, ii. 228.

STICKLEBACK, polygamous, i. 271; male, courtship of the, ii. 2; male, brilliant colouring of, during the breeding season, ii. 14; nidification of the, ii. 20.

STICKS used as implements and weapons by monkeys, i. 51.

STING in bees, i. 254.

STOKES, Capt., on the habits of the great Bower-bird, ii. 70.

STONECHAT, young of the, ii. 220.

STONE IMPLEMENTS, difficulty of making, i. 138; as traces of extinct tribes, i. 237.

STONES, used by monkeys for breaking hard fruits and as missiles, i. 140; piles of, i. 233.

STORK, black, sexual differences in the bronchi of the, ii. 60; red beak of the, ii. 227.

STORKS, ii. 226, 230; sexual difference in the colour of the eyes of, ii. 128.

STRANGE, Mr., on the Satin Bower-bird, ii. 69.

STRETCH, Mr., on the numerical proportion in the sexes of chickens, i. 306.

_Strepsiceros kudu_, horns of, ii. 255; markings of, ii. 300.

STRIDULATION, by males of _Theridion_, i. 339; of the Orthoptera and Homoptera discussed, i. 360; of beetles, i. 378.

STRIPES, retained throughout groups of birds, ii. 131; disappearance of, in adult mammals, ii. 303.

_Strix flammea_, ii. 105.

STRUCTURE, existence of unserviceable modifications of, i. 153.

STRUGGLE for existence, in man, i. 180, 185.

STRUTHERS, Dr., on the occurrence of the supra-condyloid foramen in the humerus of man, i. 28.

_Sturnella ludoviciana_, pugnacity of the male, ii. 51.

_Sturnus vulgaris_, ii. 105.

SUB-SPECIES, i. 227.

SUFFERING, in strangers, indifference of savages to, i. 94.

SUICIDE, i. 172; formerly not regarded as a crime, i. 94; rarely practised among the lowest savages, i. 94.

SUIDÆ, stripes of young, ii. 184.

SUMATRA, compression of the nose by the Malays of, ii. 352.

SUMNER, Archb., man alone capable of progressive improvement, i. 49.

SUN-BIRDS, nidification of, ii. 169.

SUPERSTITIONS, i. 182; prevalence of, i. 99.

SUPERSTITIOUS customs, i. 68.

SUPERCILIARY ridge in man, ii. 316, 318.

SUPERNUMERARY digits, more frequent in men than in women, i. 276; inheritance of, i. 285; early development of, i. 292.

SUPRA-CONDYLOID foramen in the early progenitors of man, i. 206.

SUSPICION, prevalence of, among animals, i. 39.

SULIVAN, Sir B. J., on two stallions attacking a third, ii. 241.

SWALLOW-TAIL Butterfly, i. 393.

SWALLOWS deserting their young, i. 84, 90.

SWAN, black, red beak of the, ii. 227; black-necked, ii. 230; white, young of, ii. 211; wild, trachea of the, ii. 59.

SWANS, ii. 226, 230; young, ii. 208.

SWAYSLAND, Mr., on the arrival of migratory birds, i. 259.

SWINHOE, R., on the common rat in Formosa and China, i. 50; on the sounds produced by the male Hoopoe, ii. 62; on _Dicrurus macrocercus_ and the Spoonbill, ii. 179; on the young of _Ardeola_, ii. 190; on the habits of _Turnix_, ii. 202; on the habits of _Rhynchæa bengalensis_, ii. 203; on Orioles breeding in immature plumage, ii. 214, 215.

_Sylvia atricapilla_, young of, ii. 219.

_Sylvia cinerea_, aerial love-dance of the male, ii. 68.

SYMPATHY, i. 168; among animals, i. 77; its supposed basis, i. 82.

SYMPATHIES, gradual widening of, i. 100.

SYNGNATHOUS fishes, abdominal pouch in male, i. 210.

_Sypheotides auritus_, acuminated primaries of the male, ii. 64; ear-tufts of, ii. 73.

T.

TABANIDÆ, habits of, i. 254.

_Tadorna variegata_, sexes and young of, ii. 206.

_Tadorna vulpanser_, ii. 114.

TAHITIANS, i. 183; compression of the nose by the, ii. 352.

TAIL, rudimentary, occurrence of, in man, i. 29; convoluted body in the extremity of the, i. 30; absence of, in man and the higher apes, i. 150, 194; variability of, in species of _Macacus_ and in baboons, i. 150; presence of, in the early progenitors of man, i. 206; length of, in pheasants, ii. 156, 164, 166; difference of length of the, in the two sexes of birds, ii. 164.

TAIT, Lawson, on the effects of natural selection on civilised nations, i. 168.

TANAGER, scarlet, variation in the male, ii. 126.

_Tanagra æstiva_, ii. 180; age of mature plumage in, ii. 213.

_Tanagra rubra_, ii. 126; young of, ii. 220.

_Tanais_, absence of mouth in the males of some species of, i. 255; relations of the sexes in, i. 315; dimorphic males of a species of, i. 328.

TANKERVILLE, Earl, on the battles of wild bulls, ii. 240.

_Tanysiptera_, races of, determined from adult males, ii. 190.

_Tanysiptera sylvia_, long tail-feathers of, ii. 165.

_Taphroderes distortus_, enlarged left mandible of the male, i. 344.

TAPIRS, longitudinal stripes of young, ii. 184, 303.

TARSI, dilatation of front, in male beetles, i. 343.

_Tarsius_, i. 200.

TASMANIA, half-castes killed by the natives of, i. 220.

TATTOOING, i. 232; universality of, ii. 339.

TASTE, in the Quadrumana, ii. 296.

TAYLOR, G. on _Quiscalus major_, i. 307.

TEA, fondness of monkeys for, i. 12.

TEAR-SACKS, of Ruminants, ii. 280.

TEEBAY, Mr., on changes of plumage in spangled Hamburgh fowls, i. 281.

TEETH, rudimentary incisor, in Ruminants, i. 17; posterior molar, in man, i. 25; wisdom, i. 26; diversity of, i. 108; canine, in the early progenitors of man, i. 206; canine, of male mammals, ii. 241; in man, reduced by correlation, ii. 325; staining of the, ii. 339; front, knocked out or filed by some savages, ii. 340.

TEGETMEIER, Mr., on the abundance of male pigeons, i. 306; on the wattles of game-cocks, ii. 98; on the courtship of fowls, ii. 117; on dyed pigeons, ii. 118.

TEMBETA, ii. 341.

TEMPER, in dogs and horses, inherited, i. 40.

TENCH, proportions of the sexes in the, i. 308, 309; brightness of male, during breeding season, ii. 13.

TENEBRIONIDÆ, stridulation of, i. 379.

TENNENT, Sir J. E., on the tusks of the Ceylon Elephant, ii. 248, 258; on the frequent absence of beard in the natives of Ceylon, ii. 321; on the Chinese opinion of the aspect of the Cingalese, ii. 345.

TENNYSON, A., on the control of thought, i. 101.

TENTHREDINIDÆ, proportions of the sexes in, i. 314; fighting habits of male, i. 364; difference of the sexes in, i. 365.

_Tephrodornis_, young of, ii. 190.

TERAI, i. 237.

_Termites_, habits of, i. 364.

TERNS, white, ii. 228; and black, ii. 230.

TERNS, seasonal change of plumage in, ii. 228.

TERROR, common action of, upon the lower animals and man, i. 39.

_Testudo nigra_, ii. 28.

_Tetrao cupido_, battles of, ii. 50; sexual difference in the vocal organs of, ii. 56.

_Tetrao phasianellus_, dances of, ii. 68; duration of dances of, ii. 100.

_Tetrao scoticus_, ii. 170, 185, 194.

_Tetrao tetrix_, ii. 170, 185, 194; pugnacity of the male, ii. 45.

_Tetrao umbellus_, pairing of, ii. 49; battles of, ii. 50; drumming of the male, ii. 61.

_Tetrao urogalloides_, dances of, ii. 100.

_Tetrao urogallus_, pugnacity of the male, ii. 45.

_Tetrao urophasianus_, inflation of the œsophagus in the male, ii. 57.

_Thamnobia_, young of, ii. 190.

_Thaumalea picta_, display of plumage by the male, ii. 89.

_Thecla_, sexual differences of colouring in species of, i. 389.

_Thecla rubi_, protective colouring of, i. 392.

_Theridion_, i. 337; stridulation of males of, i. 339.

_Theridion lineatum_, variability of, i. 338.

_Thomisus citreus_, and _T. floricolens_, difference of colour in the sexes of, i. 337.

THOMPSON, J. H., on the battles of sperm-whales, ii. 240.

THOMPSON, W., on the colouring of the male char during the breeding season, ii. 14; on the pugnacity of the males of _Gallinula chloropus_, ii. 41; on the finding of new mates by magpies, ii. 103; on the finding of new mates by Peregrine falcons, ii. 104.

THORAX, processes of, in male beetles, i. 370.

THORELL, T., on the proportion of the sexes in spiders, i. 315.

THORNBACK, difference in the teeth of the two sexes of the, ii. 6.

THOUGHTS, control of, i. 101.

THRUSH, pairing with a blackbird, ii. 113; colours and nidification of the, ii. 170.

THRUSHES, characters of young, ii. 185, 269.

THUG, his regrets, i. 94.

THUMB, absence of, in _Ateles_ and _Hylobates_, i. 140.

THURY, M., on the numerical proportion of male and female births among the Jews, i. 301.

_Thylacinus_, possession of the marsupial sack by the male, i. 208.

THYSANURA, i. 348.

TIBIA, dilated, of the male _Crabro cribrarius_, i. 343.

TIBIA and femur, proportions of, in the Aymara Indians, i. 119.

TIERRA del Fuego, marriage-customs of, ii. 373.

TIGER, colours and markings of the, ii. 302.

TIGERS, depopulation of districts by, in India, i. 134.

_Tillus elongatus_, difference of colour in the sexes of, i. 368.

TIMIDITY, variability of, in the same species, i. 40.

TINEINA, proportion of the sexes in, i. 310.

_Tipula_, pugnacity of male, i. 349.

TITS, sexual difference of colour in, ii. 174.

TOADS, ii. 25; male, treatment of ova by some, i. 210; male, ready to breed before the female, i. 260.

TOE, great, condition of, in the human embryo, i. 17.

TOMTIT, blue, sexual difference of colour in the, ii. 174.

TONGA Islands, beardlessness of the natives of, ii. 322, 349.

TOOKE, Horne, on language, i. 55.

TOOLS, flint, i. 183; used by monkeys, i. 51; use of, i. 137.

TOP-KNOTS in birds, ii. 74.

_Tomicus villosus_, proportion of the sexes in, i. 314.

TORTOISE, voice of the male, ii. 331.

TORTURES, submitted to by American savages, i. 95.

_Totanus_, double moult in, ii. 81.

TOUCANS, colours and nidification of the, ii. 171; beaks and ceres of the, ii. 227.

TOWNS, residence in, a cause of diminished stature, i. 115.

TOYNBEE, J., on the external shell of the ear in man, i. 21.

TRACHEA, convoluted and imbedded in the sternum, in some birds, ii. 59; structure of the, in Rhynchæa, ii. 203.

TRADES, affecting the form of the skull, i. 147.

_Tragelaphus_, sexual differences of colour in, ii. 288.

_Tragelaphus scriptus_, dorsal crest of, ii. 282; markings of, ii. 299, 300.

TRAGOPAN, i. 270; swelling of the wattles of the male, during courtship, ii. 72; display of plumage by the male, ii. 91; markings of the sexes of the, ii. 134.

_Tragops dispar_, sexual difference in the colour of, ii. 30.

TRAINING, effect of, on the mental difference between the sexes of man, ii. 329.

TRANSFER of male characters to female birds, ii. 193.

TRANSMISSION, equal, of ornamental characters, to both sexes in mammals, ii. 297.

TRAPS, avoidance of, by animals, i. 49; use of, i. 137.

TREACHERY, to comrades, avoidance of, by savages, i. 88.

_Tremex columbæ_, i. 365.

TRIBES, extinct, i. 160; extinction of, i. 236.

_Trichius_, difference of colour in the sexes of a species of, i. 368.

TRIMEN, R., on the proportion of the sexes in South African butterflies, i. 310; on the attraction of males by the female of _Lasiocampa quercus_, i. 312; on _Pneumora_, i. 358; on difference of colour in the sexes of beetles, i. 367; on moths brilliantly coloured beneath, i. 397; on mimickry in butterflies, i. 412; on _Gynanisa Isis_, and on the ocellated spots of Lepidoptera, ii. 132; on _Cyllo Leda_, ii. 133.

_Tringa_, sexes and young of, ii. 216.

_Tringa canutus_, ii. 82.

_Triphæna_, coloration of the species of, i. 395.

TRISTRAM, H. B., on unhealthy districts in North Africa, i. 244; on the habits of the chaffinch in Palestine, i. 307; on the birds of the Sahara, ii. 172; on the animals inhabiting the Sahara, ii. 224.

_Triton cristatus_, ii. 24.

_Triton palmipes_, ii. 24.

_Triton punctatus_, ii. 24, 25.

_Troglodytes vulgaris_, ii. 198.

TROGONS, colours and nidification of the, ii. 171, 173.

TROPIC-BIRDS, white only when mature, ii. 228.

TROPICS, freshwater fishes of the, ii. 17.

TROUT, proportion of the sexes in, i. 308; male, pugnacity of the, ii. 3.

_Trox sabulosus_, stridulation of, i. 380.

TRUTH, not rare between members of the same tribe, i. 95; more highly appreciated by certain tribes, i. 100.

TULLOCH, Major, on the immunity of the negro from certain fevers, i. 243.

TUMBLER, almond, change of plumage in the, i. 294.

_Turdus merula_, ii. 170; young of, ii. 219.

_Turdus migratorius_, ii. 185.

_Turdus musicus_, ii. 170.

_Turdus polyglottus_, young of, ii. 219.

_Turdus torquatus_, ii. 170.

TURKEY, swelling of the wattles of the male, ii. 72; variety of, with a top-knot, ii. 74; recognition of a dog by a, ii. 110; wild, pugnacity of young male, ii. 48; wild, notes of the, ii. 60; male, wild, acceptable to domesticated females, ii. 119; wild, first advances made by older females, ii. 121; wild, breast-tuft of bristles of the, ii. 179.

TURKEY-COCK, scraping of the wings of, upon the ground, ii. 61; wild, display of plumage by, ii. 87; fighting habits of, ii. 98.

TURNER, Prof. W., on muscular fasciculi in man referable to the panniculus carnosus, i. 19; on the occurrence of the supra-condyloid foramen in the human humerus, i. 28; on muscles attached to the coccyx in man, i. 29; on the _filum terminale_ in man, i. 30; on the variability of the muscles, i. 109; on abnormal conditions of the human uterus, i. 123; on the development of the mammary glands, i. 209; on male fishes hatching ova in their mouths, i. 210.

_Turnix_, sexes of some species of, ii. 201, 207.

TURTLE-DOVE, cooing of the, ii. 60.

TUTTLE, H., on the number of species of man, i. 226.

TYLOR, E. B., on emotional cries, gestures, &c., of man, i. 54; on the origin of the belief in spiritual agencies, i. 66; on the primitive barbarism of civilised nations, i. 181; on the origin of counting, i. 181; on resemblances of the mental characters in different races of man, i. 232.

TYPE of structure, prevalence of, i. 211.

_Typhœus_, stridulating organs of, i. 378; stridulation of, i. 380.

TWINS, tendency to produce, hereditary, i. 133.

TWITE, proportion of the sexes in the, i. 307.

U.

UGLINESS, said to consist in an approach to the lower animals, ii. 354.

UMBRELLA-BIRD, ii. 58, 59.

_Umbrina_, sounds produced by, ii. 23.

UNITED States, rate of increase in, i. 131; influence of natural selection on the progress of, i. 179; change undergone by Europeans in the, i. 246.

_Upupa epops_, sounds produced by the male, ii. 62.

URANIIDÆ, coloration of the, i. 396.

_Uria troile_, variety of, (= _U. lacrymans_), ii. 127.

URODELA, ii. 24.

_Urosticte Benjamini_, sexual differences in, ii. 151.

USE and disuse of parts, effects of, i. 116; influence of, on the races of man, i. 247.

UTERUS, reversion in the, i. 123; more or less divided, in the human subject, i. 123, 130; double, in the early progenitors of man, i. 206.