INDEX 



831 



with that of lower animals, 22 ; on 

 the adult age of the orang, 25; on 

 the embryonic development of man, 

 26; on the origin of man, 19, 28; 

 on variation in the skulls of the 

 natives of Australia, 46; on the ab- 

 ductor of the fifth metatarsal in apes, 

 65 ; on the nature of the reasoning 

 power, 109 ; on the position of man, 

 201 ; OQ the suborders of primates, 

 204; on the Lemuridae, 211; on the 

 Dinosauria, 212; on the amphibian 

 affinities of the lohthyosaurians, 

 212 ; on variability of the skull 

 m certain races of man, 232; on 

 the races of man, 235; supplement 

 on the brain, 263-273. 



Hybrid birds, production of, 535. 



Hydrophobia communicable between 

 man and the lower animals, 23. 



Hydroporus, dimorphism of females 

 of, 364. 



Hyelaphua porcinus, 501. 



Hygrogonus, 449. 



Hyla, singing species of, 455. 



Hylobales, absence of the thumb in, 

 16; upright progression of some 

 species of, 18; maternal affection 

 in a, 100-101; direction of the hair 

 on the arms of species of, 203 ; 

 females of, less hairy below than 

 males, 120. 



agilis, coherence of the toes, 16; 



hair on the arms of, downward in 

 the ordinary manuer, 203; musical 

 voice of the, 681 ; superciliary ridge 

 of, 118; voice of, 130. 



hoolock, aeiual difEerenoe of color 



in, 694. 



. lar, coherence of the toes, 16; 



hair on the arms of, in a transitional 

 state, 203. 



leuciscus, coherence of the toes, 



16 ; song of, 131. 



syndactylus, coherence of the 



toes, 16; laryngeal sac of, 681. 



Hylophila prasinana, 402. 



Hymenoptera, 382; large size of the 

 cerebral ganglia in, 80; classifica- 

 tion of, 199; sexual differences In 

 the wings of, 365; aculeate, relative 

 size of the sezea of, 361. 



Hymenopteron, parasitic, with a sed- 

 entary male, 292. 



Hyomoschus aquations, 106. 



Hyperythra, proportion of the sexes 



in, 231. 

 Hypogymna dispar, sexual difference 



of color in, 412. 

 Hypopyra,, coloration of, 411. 



Ibex, male, faUing on his horns, 656; 

 beard of the, 686. 



Ibis, white, change of color of naked 

 skin in, during the breeding season, 

 503; scarlet, young of the, 620. 



tantalus, age of mature plumage 



in, 624; breeding in immature plu- 

 mage, 625. 



Ibises, decomposed feathers in, 498; 

 white, 635; and black, 631. 



Ichneumonidse, difference of the sexes 

 in, 382. 



Ichthyopterygia, 60. 



lohthyosaurians, 212. 



Idiots, microcephalous, their characters 

 and habits, 58 ; hairiness and animal 

 nature of their actions, 58 ; micro- 

 cephalous, imitative faculties of, 

 122. 



Iguana tuberculata, 460. 



Iguanas, 460. 



Illegitimate and legitimate chUdreu, 

 proportion of the sexes in, 321. 



Imagination, existence of, in animals, 

 106-101. 



Imitation, 99; of man by monkeys, 

 104; tendency to, in monkeys, mi- 

 crocephalous idiots and savages, 122 ; 

 influence of, 114. 



Immature plumage of birds, 596, 601. 



Implacentata, 211. 



Implements, employed by monkeys, 

 114^115; fashioning of, peculiar to 

 man, 116-111. 



Impregnation, period of, influence of, 

 upon sex, 322. 



Improvement, progressive, man alone 

 supposed to be capable of, 113. 



Incisor teeth, knocked out or filed by 

 some savages, 140. 



Increase, rate of, 68 ; necessity of 

 checks in, 10-11. 



Indecency, hatred of, a modern virtue, 

 161. 



India, difficulty of distinguishing th< 

 native races of, 223 ; Oyprinidse of. 



