on the number of digits in the Ichthyopterygia, 37; on the canine teeth in man, 40; on the walking of the chimpanzee and orang, 50; on the mastoid processes in the higher apes, 53; on the hairiness of elephants in elevated districts, 57; on the caudal vertebræ of monkeys, 58; classification of mammalia, 148; on the hair in monkeys, 152; on the piscine affinities of the Ichthyosaurians, 159; on pologamy and monogamy among the antelopes, 217; on the horns of Antilocapra americana, 234; on the musky odour of crocodiles during the breeding season, 351; on the scent-glands of snakes, 352; on the Dugong, Cachalot and Ornithorhynchus, 502; on the antlers of the red deer, 510; on the dentition of the Camelidæ, 514; on the horns of the Irish elk, 515; on the voice in the giraffe, porcupine, and stag, 526; on the laryngeal sac of the gorilla and orang, 527; on the odoriferous glands of mammals, 528, 529; on the effects of emasculation on the vocal organs of men, 566; on the voice of Hylobates agilis, 567; on American monogamous monkeys, 567.
- Owls, white, new mates found by, 408.
- Oxynotus, difference of the females of two species of, 470.
P.
- Pachydermata, 218.
- Pachytylus migratorius, 283.
- Paget, on the abnormal development of hairs in man, 19; on the thickness of the skin on the soles of the feet of infants, 33.
- Painting, pleasure of savages in, 178.
- Palœmon, chelæ of a species of, 267.
- Palœornis, sexual differences of colour in, 494.
- javanicus, colour of beak of, 461.
- rosa, young of, 467.
- Palamedea cornuta, spurs on the wings, 364.
- Paleolithic period, 145.
- Palestine, habits of the chaffinch in, 248.
- Pallas, on the perfection of the senses in the Mongolians, 34; on the want of connexion between climate and the colour of the skin, 192; on the polygamous habits of Antilope Saiga, 217; on the lighter colour of horses and cattle in winter in Siberia, 229; on the tusks of the musk-deer, 513, 514; on the odoriferous glands of mammals, 529; on the odoriferous glands of the musk-deer, 530; on winter changes of colour in mammals, 542; on the ideal of female beauty in North China, 578.
- Palmaris accessorius, muscle variations of the, 27.
- Pampas, horses of the, 181.
- Pangenesis, hypothesis of, 228, 231.
- Panniculus carnosus, 13.
- Pansch, on the brain of a fœtal Cebus apella, 205.
- Papilio, proportion of the sexes in North American species of, 250; sexual differences of colouring in species of, 309; coloration of the wings in species of, 312.
- ascanius, 309.
- Sesostris and Childrenœ, variability of, 319.
- Turnus, 250.
- Papilionidæ, variability in the, 319.
- Papuans, line of separation between the, and the Malays, 169; beards of the, 560; hair of, 575.
- and Malays, contrast in characters of, 168.
- Paradise, Birds of, 405, 462; supposed by Lesson to be polygamous, 219; rattling of their quills by, 375; racket-shaped feathers in, 384; sexual differences in colour of, 385; decomposed feathers in, 385, 403; display of plumage by the male, 395.
- Paradisea apoda, barbless feathers in the tail of, 385; plumage of, 385; and P. papuana, 385; divergence of the females of, 470; increase of beauty with age, 485.
- Paraguay, Indians of, eradication of eyebrows and eyelashes by, 580.
