INDEX. 



663 



of the strldulant Orthoptera, 

 281. 

 Sight, inheritance of long and 



short, 32. 

 Signal-cries of monkeys, 85. 

 Silk-moth, proportion of the sexes 

 in, 245, 247; Allan thus, prof. 

 Canestrini, on the destruction of 

 its larvae by wasps, 247; differ- 

 ence of size of the male and fe- 

 male cocoons of the, 275; pair- 

 ing of the, 314. 

 Slmiadse, 148; their origin and 



divisions, 161. 

 Similarity, sexual, 220. 

 Singing of the Cicadse and Ful- 

 gorldas, 279; of tree-frogs, 346; 

 of birds, object of the, 364. 

 Slrenia, nakedness of, 54. 

 Sirex juvencus, 289. 

 Siricldse, difference of the sexes 



in, 289. 

 Siskin, 388; pairing with a canary, 



410. 

 Sltana, throat-pouch of the males 



of, 350, 353. 

 Size, relative, of the sexes of in- 

 sects, 275. 

 Skin, movement of the, 13; naked- 

 ness of, in man, 54; color of the, 

 187. 

 and hair, correlation of col- 

 or of, 192. 

 Skull, variation of, in man, 25; 

 cubic contents of, no absolute 

 test of Intellect, 52; Neanderthal, 

 capacity of the, 53; causes of 

 modification of the, 53; differ- 

 ence of. In form and capacity. 

 In different races of men 164; 

 variability of the shape of the, 

 170; differences of, in the sexes 

 in man, 552; artificial modifica- 

 tion of the shape of, 569. 

 Skunk, odor emitted by the, 524; 



white tall of, protective, 538. 

 Slavery, prevalence of, 114; of wo- 

 men, 588. 

 Slaves, difference between field 



and house-slaves, 191. 

 Sloth, ornaments of male, 529. 

 Smell, sense of, in man and ani- 

 mals, 17. 

 Smith, Adam, on the basis of sym- 

 pathy, 103. 



, Sir A., on the recognition 



of women by male Cynocephali, 

 8; on revenge by a baboon, 67; 

 on an instance of memory in a 

 baboon, 72; on the retention of 

 their color by the Dutch in 

 South Africa, 188; on the polyg- 

 amy of the South African an- 

 telopes, 213; on the polygamy of 

 the lion, 214; on the proportion 

 of the sexes In Kobus ellipsip- 

 rymnus, 242; on Bucephalus ca- 

 pensis, 347; on South African liz- 

 ards, 353; on fighting gnus, 497; 

 on the horns of rhinoceroses, 

 601; on the fighting of lions, 516; 



on the colors of the Cape Bland, 

 531; on the colors of the gnu, 

 631; on Hottentot notions of 

 beauty, 573; disbelief in commu- 

 nistic marriages, 583. 



Smith, F., on the Cynipidaj and 

 Tenthredlnlds5, 250; on the rela- 

 tive size of the sexes of Acule- 

 ate Hymenoptera, 277; on the 

 difference between the sexes of 

 ants and bees, 289; on the stridu- 

 lation of Trox sabulosus, 300; on 

 the stridulation of Mononychua 

 pseudacori, 302. 



Smynthurus luteus, courtship of. 

 277. 



Snakes, sexual differences of, 

 347; mental powers of, 348; male, 

 ardency of, 348. 



"Snarling muscles," 39. 



Snipe, drumming of the, 372; col- 

 oration of the, 486. 



, painted, sexes and young 



of, 470. 



, solitary, assemblies of, 400. 



Snipes, arrival of male before the 

 female, 208; pugnacity of male, 

 358; double moult in, 385. 



Snow-goose, whiteness of the, 488. 



Social animals, affection of, for 

 each other, 97; defense of, by the 

 males, 104. 



Sociability, the sense of duty con- 

 nected with, 95; Impulse to, In 

 animals, 102 r manifestations of, 

 in man, 105; instinct of, in ani- 

 mals, 106. 



Sociality, probable, of primeval 

 men, 60; influence of, on the de- 

 velopment of the Intellectual 

 faculties, 125; origin of, in man, 

 126. 



Soldiers, American, measurements 

 of. 31. 



and sailors, difference In the 



proportions of, 31. 



Solenostoma, bright colors and 

 marsupial sack of the females 

 of, 342. 



Song of male birds appreciated by 

 their females, 89; want of, in 

 brilliant plumaged birds, 395; of 

 birds, 444. 



Sorex, odor of, 523. 



Sounds admired alike by man and 

 animals, 90; produced by fishes, 

 343; produced by male frogs and 

 toads, 346; instrumentally pro- 

 duced by birds, 371 et seq. 



Spain, decadence of, 137. 



Sparassus smaragdulus, difference 

 of color in the sexes of, 268. 



Sparrow, pugnacity of the male, 

 356; acquisition of the Linnet's 

 song by a, 366; coloration of the, 

 467; immature plumage of the, 

 461. 



, white-crowned, young of 



the, 481. 



Sparrows, house- and tree-, 449. 



