INDEX. 



677 



Size, relative, of the sexes of insects, 

 278. 



Si in, movement of the, 13; naked- 

 ness of, m man, 36 ; colour o^ the, 

 192. 



— — and hair, corielatlon of colour 

 of, 197. 



Bkull, variation of, in man, 26 ; 

 cubic contents of, no absolute test 

 of intellect, 54; Neanderthal, ca- 

 pacity of the, 55 ; causes of modi- 

 Kcation of the, 55; difference of, 

 in form and capacity, in different 

 races of men, 168; variability of 

 the shape of the, 174 ; differences 

 of, in the sexes in man, 557 ; arti- 

 ficial modification of the shape of, 

 575. 



Sliunli, odour emitted by the, 528 ; 

 white tail of, protective, 543. 



Slavery, prevalence of, 117 ; of wo- 

 men, 593. 



Slaves, difference between field and 

 houi-e-slaves, 196. 



Sloth, ornaments of male, 534. 



Smell, sense of', in man and animals, 

 17. 



Smith, Adam, on the basis of sym- 

 pathy, lUB. 



, Sir A , on the recognition of 



women by male Cynocep/ia'if 8 ; on 

 revenge by a baboon, 69 ; on an 

 instance of memory in a baboon, 

 74 ; on the retention of their colour 

 by the Dutch in South Africa, 193 ; 

 on the polygamy of the South 

 African antelopes, 217; on the 

 polygamy of the lion, 218; on the 

 proportion of the sexes in Kdbus 

 ellipsiprymnus, 247 ; on Btiaephalus 

 capensis, 351 ; on South African 

 lizards, 358; on fighting gnus, 

 501 ; on the horns of rhinoceroses, 

 500 ; on the fighting of lions, 521 ; 

 on i.he coloui-s of the Cape Eland, 

 535; on the colours of the gnu, 

 536; on Hottentot notions of 

 beauty, 578; disbelief in commu- 

 nistic marriages, 588. 



r, J F., on the Cympida; and Ten- 



thrcdinidip. 254; on the relative 

 size of the sexes of Aculeate Hymen- 

 o]itera, 279; on the ditlcreuce be- 

 tween the sexis of ants and bees, 

 392 i on the stridulation of Trox 



sabulosus, 303; en the stridulstion 

 of Mononyc/ius pseudacori^ 305. 



Smynt/mrus luteus, courtship of, 279. 



Snalces, sexual differences of, 351 ; 

 mental powers of, 352 ; male, ar- 

 dency of, 352. 



** Snarling muscles," 41. 



Snipe, drumming of the, 376 ; colo- 

 ration of the, 491. 



, painted, sexes and young of, 



476. 



, solitary, assemblies of, 405. 



Snipes, arrival of male before the 

 female, 212 ; pugnacity of male, 

 362; double moult in, 390. 



Snow-goose, whiteness of the, 492. 



Social animals, affection of, for each 

 other, 102; defence of, by the 

 males, 107. 



Sociability, the sense of duty con- 

 nected with, 98 ; impulse to, in 

 animals, 105 ; manifestations of, 

 in man, 108 ; instinct of, in ani- 

 mals, 109. 



Sociality, probable, of primeval men, 

 62; influence of, on the develop- 

 ment of the intellectual faculties, 

 128 ; origin of, in man, 129. 



Soldiers, American, measurements of, 

 29. 



and sailors, difference in the 



proportions of, 32. 



Solenostoma, bright colours and mar- 

 supial sack of the females of, 

 346. 



Song of male birds appreciated by 

 their females, 92 ; want of, in 

 brilliant plumaged birds, 401 ; of 

 birds, 450. 



Sorex, odour of, 528. 



Sounds admired alike by man and 

 animals, 92 ; produced by fishes, 

 347 ; produced by male frogs and 

 toads, 350 ; instrumentally pro- 

 duced by birds, 376 et seq, 



Spain, decadence of, 141. 



Bparassus smaragdulus, difference of 

 colour in the sexes of, 272. 



Sparrow, pugnacity of the male, 360 ; 

 acquisition of the Linnet*s song i>y 

 a, 370 ; coloration of the, 473 ; im- 

 mature plumage of the, 466. 



, white-crowned, young of the, 



486. 

 Sparrows, house- and tree-, 455. 



