Preface -- Preface to the second edition -- pt. I. The meaning of heredity. 1, Introduction. 2, In the beginnning. 3, The laws of inheritance. 4, "Blood is thicker than water." 5, Heredity and environment. 6, The effects of environment upon the developing human being in the womb. 7, Environment after birth. 8, Twins, genes, and environment. 9, Crime-genes or environment or both? 10, Genes and constitution. 11, Sex. 12, Heredity and "race" -- pt. II. The family album. 13, The pigmentary system of the skin, eyes, and hair. 14, The features. 15, The body. 16, Heredity and blood. 17, What do we do about heredity? 18, The bomb, radiation, and human heredity -- App. A. Inherited disorders of man -- App. B. The chance of the offspring of marriage between cousins exhibiting a defective conditon -- App. C. Gene and genotype equilibria, populations and genes, the Hardy-Weinberg law -- App. D. Location, name of institution, and principal counselor of some heredity clinics (by state) -- App. E. Glossary -- App. F. Genetics in the U.S.S.R.: a political "science." Books for further reading. Bibliography. Index.