INDEX 



287 



Thyroid, action of, 215, 216, 217 



and personality, 219 



and size, 32 



cancer in, of rats, 140 



composition of, 214 

 Thyroxin, 214, 216 

 Timidity, inheritance of, 167 

 Tissue cultures, 41 

 Titles, hereditary, 222 

 Tomatoes, bush varieties, 35 

 Toothache in twins, 188 

 Tooth anomalies, 55, 97, 102, 124, 



130, 222, 236 

 Toothless families, 71 

 Tortoiseshell-coloured eyes, 49 

 Tradition, 205, 225, 226, 247, 248, 



249 

 Transforrhation of sex, 131, 132 

 Tremor, hereditary, 108 

 Tribal differences, loss of, 223 

 Triplets, 197, 198, 199 

 Triploid chromosome numbers, 



21 

 Trivial characters, 207 

 Troph oedema, 127 

 Tuberculosis, 123, 139 



in crossed races, 231 



in negroes, 235 

 Tumbling in pigeons, 167 

 Tumours from nerves, 141 



in Drosophila, 140 



in pituitary, 212 



sebaceous, 123 

 Tupper, W, W., 42 

 Tiirdus migratorius, 68 

 Turkeys, wild, 39 

 Turnspit dog, 41 

 Twin embryos, production of, 177, 



178 

 Twinning, influence of father on, 



195 

 inheritance of, 194 

 Twins, 76, 146, 173, 175, 176, 178, 

 179, 180, 182-193 

 effect of separation, 1 90 

 in cattle, 198, 201, 202, 203 

 ■ in fishes, 177 

 origin of identical, 199 

 two types, 1 98 



U 



Uhlenhuth, E., 41 



Unconscious repression, 165 



Unilateral inheritance, 135, 136 



Uniovular twins, 180 



United States, 237, 250 



Anglo-Saxons in, 245 

 arable land in, 245 



United' States, births in, 200 



crossingin, 230, 232,233, 



236 

 feeblemindedness in, 152, 



159 

 negro in, 233, 234 

 pellagra in, 122 

 population of, 245 



Urquhart, A. R., 156 



Usher, C. H., 44, 57, 61 



Uxbridge, 91 



■ V 



Variation, i , 5,6, 7 



blastogenic, 181 



continuity in, 27, i:;!, 17^, 

 184 



discontinuity in, 27, 175 



in Canidae, 125 



in hybrid race, 229 



in mammals, 125 



in man, 21 1 

 Vegetables, bush varieties of, 35 



run wild, 39 

 Venereal disease in negro troops, 



235 

 Vermont, 104 



Vigour from crossing, 29, 206, 223 



in twins, 188 



Vineland Institution, 1 50 



Virginia, 89 



Vitamines, 42 



Voice in twins, 187, 189, 190 



W 



Walker, 20, 84, 88 

 Wallace, A. R., 100, 228, 240 

 Walnut hybrids, 205 

 Waltzing in mice, 167 

 Warren, H. C, 207 

 Warts on the hands, 123 



inheritance of, 123 

 Washington, Booker T., 235 

 Weakening of a character by 



exogamy, 104 

 Webbing. " See Syndactyly 

 Weeks, 158 

 Wegelin, Carl, 91 

 Weidenreich, 100 

 Weight in twins, 187, 189 

 Weinberg, 107, 108 

 Weismann, 144 

 West Indies, 94 

 Wheat, bush varieties of, 35 



chromosomes of, 22 



pure lines in, 221 

 Whisson, Rev. Mr., 112 

 Whitchurch, Sy 



