IXDEX 



491 



Eook and crow, 2 



Eoses, Mr. Baker on varieties of, 77 



Rubus, Bentliam and Babingtou on 



species and varieties of, 77 

 Rudiments and variations iu man, 



446 

 Eunts, 91 

 Rutacete, variation of structure iu, 



79 



S 



St. Helena, destruction of forests by- 

 goats, 17 

 St. Hilaire, M. Aug., variability of 



Gompliia oleafolia, 79 

 Saxicola, divergence of character iu 

 species of, 108 

 recognition marks of, 222 

 Scientific opinion before Damin, 4 

 Scolopax, ligures of tails of, 225 

 Scudder, Mr. S. H., on inedibility of 

 Danais archippus, 238 

 on fossil insects, 403 

 Seebobm, Mr. , on swamping effects of 



intercrossing, 143 

 Seeds, how dispersed, 306 

 how protected, 307 

 floating great distances, 361 

 dispersal of, by wind, 362 

 weight and dimensions of, 364 

 importance of wind-carriage of, 



372 

 remarkable case of wind-carriage 

 of, 373 

 Seiurus caroliuensis, diagram of varia- 

 tion, 67 

 sp., habits of, 117 

 Selection, artificial, 84 



by man, circumstances favour- 

 able to, 96 

 unconscious, 96 

 Selective association, isolation by, 



171 

 Self- fertilisation of flowers, 321 

 Semper, Professor, on casting hairs of 

 lejitiles and crustacea, 137 

 (note) 

 on direct influence of environ- 

 ment, 426 

 Sesiidge, mimicry by, 240 

 Sex colour and nests of birds, 277 



Sex, colours characteristic of, 269 

 Sexual colours of insects, probable 

 causes of, 273 

 of birds, 275 



characters due to natural selec- 

 tion, 283 

 diversity the cause of variation, 

 439 

 Sexual selection and colour, 274 

 by struggles of males, 282 

 neutralised by natural selection, 



294-296 

 restricted to male struggles, 296 

 Shetland Islands, variety of ghost- 

 moth in, 270 

 Shrews and field-mice, internal varia- 

 tions of, 69 

 Shrikes, recognition marks of, 222 

 Similarity of forms of life not due to 

 similarity of conditions, 339 

 Singing of male birds, use of, 284 

 SkuU of wolf, diagram of variations 

 of, 70 

 of Ursus labiatus, diagram of 



variations of, 72 

 of Sus cristatus, diagi-am of 

 variations of, 73 

 Skunk an illustration of -warning 



colour, 233 

 Slack, Baron von, on protective 



markings of sloths, 201 

 Sloth, protective colour and marking 



of, 201 

 Snakes, mimicry of poisonous, 261 

 Snipe, tails of two species (figs.), 



225 

 Sounds and odours peculiar to male, 

 how useful, 284 

 produced by peculiar feathers, 

 284 

 South America, fossil and recent 



mammals of, 393 

 Species, definition of, 1, 2 

 origin of, 2, 6 

 Lyell on, 4 

 Agassiz on, 5 

 transmutation of, 6 

 Geoffrey St. Hilaire on, 6 

 Dean Herbert on, 6 

 Professor Grant on, 6 

 Von Buch on, 6 

 allied, found in distinct areas, 

 36 



