538 



INDEX 



Heart, embryonic, 53, 54, 58, 59, 60, 

 63,64 



of fishes, 61 , 62-64 

 Heat, see Energy; Temperature 

 Hedgehog, 192 



European, 120 

 Height, see Body size; Stature 

 Hellbaum, H. W., 372 

 Heme, 103 

 Hemichordate, 150 

 Hemignathits, liicidus, 301, 302 



obscurus, 300, 301, 302 



M'ilsoni, 302 

 Hemiptera, 36 

 Hemoglobin, 103 

 Henderson Island, 286-287 

 Henle's loop, 92, 100 

 Heredity, 10 



of acquired characters, 14, 340-346, 

 358, 420-424 



mechanisms of, see Mendelian inherit- 

 ance 



natural selection and, see Natural se- 

 lection 



and population genetics, see Popula- 

 tion genetics 



See also Genes; Mutations 

 L'Heritier, P., 457, 458, 462, 463, 482 

 Hermaphroditism, 420 

 Hesse, 276 



Heterogony, see Allometry 

 Heterosis, see Hybrid vigor 

 Heterozygotes, 332, 333 



calculating frequency of, 433-434 



importance of, 346-347, 369, 436, 439 



superiority of, experiments in. 457-469 



viability of. 360. 467 

 Heyerdahl, T., 285, 305 

 Hibernation, 185, 267 

 Hind gut, 53, 54, 63 

 Hind limb, see Limbs 

 Hipparion, 204, 205 

 Hog, limb of, 22-2J 

 Holmes, A., 138, 142 

 Home, see Territories 

 Homeostasis, genetic, 466—469 

 Hominid. see Man, evolution of 

 Hominidae, 228, 234, 312 

 Homo, erectits, 238, 249, 250 



neanderthalensis, 244, 249 



sapiens, 224, 225, 238, 249, 312; char- 

 acteristics of, 228-232, 245; early, 

 242; races of, 250-255 



sapiens neanderthalensis, 244 



transvaalensis, 235, 250 

 See also Man 

 Homology, 21-26, 28-29, 313 



in brain structure, 32-33 



Homology {Continued) 

 in embryos. 45-50. 46 

 in invertebrates, 33-36 

 serial, 36-40 



of serum proteins, 1 10-113 

 in skull structure, 30-32 

 See also Similarity 

 Homozygotes, 332, 333 



See also Heredity; Pure lines 

 Honey creeper, 297 



See also Drepanid birds 

 Honeybee, 274 



mouth parts of, 33-^-^ 

 See also Bee 

 Hoof, see Limbs 

 Hopkins, D. M., 268, 278 

 Horn, growth of, see Allometry 

 HoroteHc rate. 501 



See also Evolutionary change, 

 rates of 

 Horse, 28 



adaptations of modern, 197-200 



brain of. 203 



evolution of. 197-206, 268, 341, 359, 



408, 409, 410. 411-413, 417 

 extinction of in North America, 206 

 family tree of, 204 

 limbs of, see Limbs 

 nictitating membrane of, 42, 43 

 reversion in, 76-77 

 skull of, see Skull 

 teeth of, see Teeth 

 transitional stages in, 202-206 

 vestiges in, 23, 42, 43 



See also Eqiiiis; Hyracotherium 

 Hot springs, preadaptation for, 453 

 Housefly, 401,451 

 mouth parts of. 35, 36 

 reproductive rate of, 352 

 See also Fly 

 Howell, F. C, 242. 256 

 Hubbs, C. L., 477, 482 

 Hubricht, L., 478, 481 

 Humans, see Man 

 Hiirzeler, J., 228, 256 

 Hussey, R. C, 133, 142, 172, 175, 217 

 Huxley, Julian, 78, 257, 274, 278, 328, 

 363, 374, 404, 405, 406, 411, 425, 

 449, 483, 492, 493, 494, 506, 507 

 Huxley, T. H., 80 

 Hybrid environment, see Environment, 



hybrid 

 Hybrid habitat, see Environment, hybrid 

 Hybrid swarm, 479 

 Hybrid vigor. 459, 463 



See also Heterozygotes 

 Hybridization, 249, 317, 321, 335, 419, 

 471-473,493 



