INDEX 



467 



Hermit-crabs, 65, 67, 73, 226 



- behaviour of, 172 

 Herodotus, 73 

 Heron- Allen, 174, 175 

 Herrick, F. H., 123 

 Heteropods, 260 

 Hexacanths, 236 

 Hibernation, 146, 153 

 Hickson, 71, 196 

 Hippocampus, 117 . 

 Hippocrates, 367 

 Hirudinea, 241 

 Hirudo medicinalis , 241 

 His, 400 



Hive-bees, 80, 171 

 Hoge, 404 



Holmes, 165 

 Holothuroids, 243, 245 

 Homes of animals, 130 

 Homing of bees, 171 

 Homologous organs, 207, 208 

 Homology, 207 

 Homoplasty, 209 

 Homoiothermal, 145 

 Homozygons, 370 

 Honey ants, 86 

 Honeycomb stomach, 149 

 Hormones, 154, 206, 315 

 Hornbill, 121 

 Horned toad, 282 

 Hornet and mimetic bug, 61 

 Horsehair worms, 238 

 Horse-leech, 241 

 Horse, pedigree of, 343 

 reversion in, 364 

 House-martin, 132 

 Houssay, 125 

 Hudson, C. T., 2 

 Humble-bees, 29, 128, 238 

 Hume, 338 



Humming-bird moth, 62 

 Humming-birds, 15, 62, 290 

 Hunter, 391 



Hunting among animals, 125 

 Huxley, 36, 97, 181, 183, 426 



- Jxilian S., 41 

 Hybrid cockatoos, 371 

 Hydatina senta, 201 



Hydra, 75, 141, 227, 299, 334 

 Hydractinia, 74, 75, 76, 227 



Hydroids, 228 

 Hydrophis, 285 

 Hypnosis, animal, 71 

 Hypoblast, 314 

 Hyrax, 294 



Ichneumon flies, 67 



Ichthyosaurus, 281 



Iguana, 282 



Imago, 324 



Immortality of Protozoa, 193 



of simple animals, 332 

 Imperfection of geological re- 

 cord, 347 



Inbreeding, 430 

 Industries of animals, 125-37 

 Indirect development, 246 

 Influence of animals on the 

 earth, 22 



of darkness, 395 



of function and environment, 

 383-410 



of light, 395 



of surroundings, 398 



of temperature, 393 

 Infusorians, 33, 220 



behaviour of, 1 65 

 Inheritance, 363 



modes of, 370 

 Ink of cuttlefish, 71 

 Insectivora, 294 

 Insects, 252, 253 



and flowers, 28 



injurious, 28, 29 



love-play of, 105 

 Instinct and intelligence, 170 

 Instinctive behaviour, 167 



- processes, 330 

 Instincts, characters of, 168 

 Insulation, 48 

 Integrates, 99 

 Integration, 205, 315 

 Intelligence and instinct, 170 

 Intelligent behaviour, 171 

 Interactions, complex, 28 

 Intercellular bridges, 204 

 Internal secretion, 183 

 Interrelations of plants and 



animals, 19 

 Intra cellular digestion, 147 



