532 



INDEX 



maturation, fertilization 

 and cleavage, 119, 120, 



m 



posterior half-embryos, S20 

 Summation of Stimuli, 57 

 Sumneh, effect of cold on mice, 



349, 500 

 Superman, 412, 439 

 Sweden, extinct noble families, 



436 

 Swine, wild and domestic, SIS 

 Symmetry, 168-170 

 Synapsis, 131 

 Syndactylism, 199, 293 



Tadpoles, fed on thyroid, thy- 

 mus, adrenal, 326 



Talents, unused, 471 

 parable of, 473 



Temperament, inheritance of, 

 205, 291 



Temperature, influence on mu- 

 tation, 310 

 influence on cell division, 

 311 



Tejtebrio, sex differentiation in, 

 IJfS 



Tennent, modified dominance 

 in echinoderm hybrids, 267, 

 500 



Teratological characters inheri- 

 ted, 199 



Tertdlliajt, 41 



Tetrads, 135 



Thompsost, cross of yellow X 

 green peas, Z^Q 

 diagram of Galton's 1st 

 Law, me, 495 



Thomsen's disease, 295 



Thoendike, behavior of dogs, 

 cats, monkeys, 64, 495 



"Thoroughbreds," 415 



Thymus gland, fed to tadpoles, 

 326 



Thyroid, effects on development, 

 331 

 gland, fed to tadpoles, 326 



Totipotence, of cleavage cells, 



316, 318, 332 

 ToWEK, action of selection", 379 



mutations in Leptinotarsa, 

 310, 311, 348, Sn 

 Traducianism, 41 

 Training of animals, 69 

 Transmission hypothesis, 91, 92, 

 Treasury of Human Inheri- 

 tance, 294, 495 

 Trial and Error, 63 

 Trihybrid, 243, 244, ^^5,381 

 Triplets, hereditary, 204 

 Trophic correlations, 329 

 Tkopisms, 52-56 

 TscHERMAK, rediscovery of 



"Mendel's Law," 224 

 Tuberculosis, inheritance of, 



201, 203 

 Turbellarian type of egg, 1118 

 Twins, fraternal, 324 



hereditary, 204 



identical, 213, S2S, 358, 457 



Ultra-microscopic units, 100 

 Uniqueness of every individual, 



155, 312, 213 

 Unit Characters, 250, 352, 353 

 Units of living matter, 97-102 



ultra microscopic, 100 



units of growth and di- 

 vision, 98, ^^ 



units of heredity, 99-103 

 Unity of organism, 46 

 Universal laws, 451 

 Use and disuse, effects of, 329 



effects not inherited, 339 

 Uterus, attachment of oosperm 



to, SI 



Variability, caused by environ- 

 ment, 388 



Variations, continuous, 210 

 discontinuous, 210 

 fluctuations, 311, 212 

 merlstic, 210 

 mutations, 311, 212 

 "sports," 210 



