358 



Index 



Punnett, 82, 101, 103 

 "Pure lines," 254, 256 

 Puritans and Cavaliers disappearing, 



293 

 Purity of germ cells, 87, 98 

 Pythagoras, on transmigration, 33 



Race amalgamation, 284 



extermination, 274 



improvement, 4, 280, 322, 325 



preservation, 322 

 Radium, disintegration of atom, 270 



influence on spermatozoa, 210 

 Rana, grafted tadpoles of, 230, 231 

 Reactions, of germ cells, 38, 42 



machine-like, 312 



Reason, 45-49 

 Reception cone, 12, 136 

 Recessive characters, 83 



"extracted," 85 



ratio to dominant, 83, 87 

 Reduction of chromosomes, 151-156 

 Reflexes, 39, 40, 42 

 Regeneration, in eggs and adults, 215, 



219 

 Reproduction, 8, 30 

 Responses, useful, 46 



varied, 50 

 Responsibility, 301, 313 



definition of, 313 



of society, 314, 321 



varied, 314 

 Retinal degeneration, 118 

 Retzius, human spermatozoa, 9, // 

 Reversible changes not inherited, 236, 



254 

 Reversion, 73, 254 

 Richards, mitosis in Fundulus, 20 

 Rickets, not inherited, 229, 230 

 Riddle, Sex determination, 167 

 Rigidity of behavior, 51 

 Rignano, "Centro-epigenesis" theory, 



235 

 Romanes, 248-253 



cattle, 253 



fowls, 250, 251 



pigeons, 248, 249 



swine, 252 

 Rome, decay of, 322, 323 

 Rosanoff, insanity inherited, 71 

 Rotifiers, induction effect of alcohol, 

 236 



Salamanders, effects of colored soil 



on, 236 

 Savagery, 243, 272 

 Scholars, prize, 283 

 Schultze, double frog embryos, 215 

 Science, duty of, 319 

 Segregation, 98 



apparent lack of, 107-111 



unusual ratios, 107 



blending of color, 108 



blending of size, no 



fundamental to Mendelism, 106 



of Mendelian factors, 98, 106 



of substance in cells, 140, 200 

 Selective Breeding, only method of 

 improving race, 275 



Spartan method, 276 

 Selection, value in Evolution, 254, 260 

 Selective Mating, 288 

 Self-knowledge and Self-control, 317, 



325 

 "Self differentiation," 225 

 Self discovery, 317 

 Semon, "Mneme" theory, 235 

 Sensitive periods, 209 

 Sensitivity, 37 



differential, 37 

 general, 38 

 of embryo, 38 

 of germ cells, 37 

 Sex, a Mendelian character, 90, 163, 

 164 

 influence of food and tempera- 

 ture, 165 

 Sex cells, fundamentally alike, 10 

 Sex determination, 157 

 in human embryo, 157 

 in man, 161, 162 

 in Ascaris, 160 

 in Protenor, 158 

 in Tenebrio, 150 



chromosomal determination, 157 

 XO type, 157 

 XY Type, 159 

 Environmental influence, 164 

 alteration of sex ratios, 164 

 hermaphrodites and inter- 

 sexes, 166 

 McClung on, 158 

 Wilson on, 158, 159 

 Stevens on, 159 



