INDEX. 



335 



Comte, the law of three stages, 30. 

 Condillac, on divided consciousness, 



305. 

 Condor, night, 108. 

 Consciousness, in instinct, 65; di- 

 vision of, 303 ; limits of, 305. 

 Constructive arts, 152. 

 Coquetry, 244, 283. 

 Courtship, 97, 99, 106, 130, 135, 145, 



211. 

 Cows, fighting play, 144 ; mass 



play, 208; an execution, 209; 



curiosity, 216. 

 Coyness, 243, 283. 

 Crane, flight, 108; courtship play, 



261 ; intelligence, 262 ; dancing, 



263. 

 Created fly-catcher, nest-building, 



159. 

 Crested lark, imitation, 199. 

 Crocodile, curiosity, 220. 

 Crossbill, flight, 216. 

 Crow, thieving, 159 ; imitation, 183 ; 



execution, 209, 211. 

 Cuckoo, love play, 270; coquetry, 



219. 

 Curiosity, 185, 214. 



Dancing, 268. 



Darwin, Charles, on instinct, 25, 46, 

 67 ; inheritance of acqnired char- 

 acters, 44, 59 ; instinct and intelli- 

 gence, 67 ; play of adults, 81 ; 

 flight of condor, 109 ; play with 

 prey, 121, 123 ; chasing play of 

 monkeys, 134; fighting plays of 

 Tetrao umbellus, 146 ; weaver 

 bird, 156; viscacha, 158; bower 

 bird, 161 ; feeling for beauty 

 among animals, 239; sexual se- 

 lection, 281, 246; imitation by 

 wolves and dogs, 190; chickens 

 learning to drink, 195 ; execution 

 by animals, 210 ; curiosity of 

 monkeys, 215; dancing of the 

 Tetrao phasianellus, 264; court- 



ship of mammals, 266 ; vanity of 

 peacocks, 267; Kupicola crocea, 

 268 ; display of plumage by va- 

 rious birds, 269, 270; musical 

 monkeys and mice, 274: bird 

 song out of pairing season, 280 ; 

 song of females, 280, 281. 



Darwin, Francis, Hylobates leu- 

 ciscus, 273. 



Decoration, 162, 327. 



Deer-hunting, play, 128. 



Delaistre, curiosity of weasels, 217. 



Descartes, animals as automata, 26. 



Dessoir, double personality, 306, 

 307 ; Binet's experiment, 313. 



Destructive impulse, 91, 200, 220. 



Dickens, on ravens, 95, 202. 



Diezel, love plays of does, 257 ; 

 army snipes, 282. 



Dittman, imitation by a starling, 

 201. 



Doe, aesthetic perception, 227 ; 

 courtship, 257. 



Dogs, tussling, 19, 141, 146, 148; 

 play with lifeless prey, 19, 132, 

 165 ; experimentation, 85, 91, 97 ; 

 voice practice, 97 ; coasting, 115 ; 

 movement plays, 116 ; play with 

 beetle, 123; hunting plays, 118; 

 deception, 119, 301 ; an artistic 

 dog, 165 ; nursing play, 170 ; imi- 

 tation, 181, 188, 191 ; curiosity, 

 215; pairing plays, 254; court- 

 ship, 257, 267 ; conscious self-de- 

 ception in fighting play, 300. 



Doll, 169. 



Dolphin, movement play, 111; teas- 

 ing, 138. 



Donkey, movement play, 113 ; fight- 

 ing play, 144. 



Double personality, 313, 314. 



Dream, relation to play, 309. 



Drongo paradisier, imitation, 200. 



Duckbill, tussling, 142. 



Ducks, learning to swim, 106 ; mass 

 plays, 211. 



