Intersexes in moths. Bird intersexes. Higher metabolism of males. Quantitative difference between sex factors. Old ideas of intersexuality. Modern surgery and human intersexes. Quantitative theory a Mendelian explanation. Peculiar complication in the case of man. Chemical life-cycles of the sexes. Functional-reproductive period and the sex problem. Relative significance of physiological sex differences. IV. SEX SPECIALIZATION AND GROUP SURVIVAL Adaptation and specialization. Reproduction a group--not an individual problem. Conflict between specialization and adaptation. Intelligence makes for economy in adjustment to environment. Reproduction, not production, the chief factor in the sex problem. V. RACIAL DEGENERATION AND THE NECESSITY FOR RATIONALIZATION OF THE MORES Racial decay in modern society. Purely "moral" control dysgenic in civilized society. New machinery for social control. Mistaken notion that reproduction is an individual problem. Economic and other factors in the group problem of reproduction. PART II BY IVA LOWTHER PETERS, PH.D. THE INSTITUTIONALIZED SEX TABOO I. THE PRIMITIVE ATTITUDE TOWARD SEX AND WOMANHOOD Primitive social control. Its rigidity. Its necessity. The universality of this control in the form of taboos. Connection between the universal attitude of primitive peoples toward woman as shown in the Institutionalized Sex Taboo and the magico-religious belief in Mana. Relation of Mana to Taboo. Discussion of Sympathetic Magic and the associated idea of danger from contact. Difficulties in the way of an inclusive definition of Taboo. Its dual nature. Comparison of concepts of Crawley, Frazer, Marett, and others. Conclusion that Taboo is Negative Mana. Contribution of modern psychology to the study of Taboo. Freud's analogy between the dualistic attitude toward the tabooed object and the ambivalence of the emotions. The understanding of this dualism together with the primitive belief in Mana and Sympathetic Magic explains much in the attitude of man toward woman. The vast amount of evidence in the taboos of many peoples of dualism in the attitude toward woman. Possible physiological explanation of this dualistic attitude of man toward woman found in a period before self-control had in some measure replaced social control, in the reaction of weakness and disgust following sex festivals. II. FROM THE DAWN OF HISTORY: WOMAN AS SAINT AND WITCH