xvi CONTENTS 



CHAPTER FAGB 



XIV. THE APPLICATION TO MAN 296 



1. The application of genetics to man . . . .296 



2. Modifying factors in the case of man . . . .297 



3. Experiments in human heredity 299 



a. The Jukes 299 



b. The descendants of Jonathan Edwards . . 301 



c. The Kallikak family 302 



4. Moral and mental characters behave like physical 



ones 303 



5. The character of human traits 304 



6. Hereditary defects 306 



7. The control of defects 309 



XV. HUMAN CONSERVATION 314 



1. How mankind may be improved 314 



2. Human assets and liabilities 315 



3. More facts needed 317 



4. Further application of what we know, necessary 319 



5. The restriction of undesirable germplasm . . . 320 



a. Control of immigration 322 



b. More discriminating marriage laws . . . 324 



c. An educated sentiment 325 



d. Segregation of defectives 327 



e. Drastic measures 329 



6. The conservation of desirable germplasm . . . 330 



a. By enlarging individual opportunity . . . 331 



b. By preventing germinal waste 331 



a. Preventable death 331 



6. Social hindrances 



c. By subsidizing the fit 333 



7. Who shall sit in judgment? 334 



8. Eugenics not "bluegenics" 335 



9. The moral 336 



BIBLIOGRAPHY 337 



INDEX 941 



