Only within the past few years have the general phenomena of intersexuality been cleared up to any considerable extent--naturally on the basis of the secretory explanation of sex. This secretory or endocrine idea has also given us an entirely new view of sex differences. These are best discussed as functional rather than as structural. To correlate this material, we must next give a rude sketch of the quantitative theory of sex. BIBLIOGRAPHY FOR CHAPTER II 1. Goldschmidt, R. Intersexuality and the Endocrine Aspect of Sex. Endocrinology, Vol. I, p. 434, 1917. 2. Bell, Dr Blair. The Sex Complex. London, 1916, p. 98. 3. Paton, D. Noël. Regulators of Metabolism. London, 1913, p. 146. 4. Goodale, H.D. Gonadectomy...Carnegie Pub. 243, 1916, pp. 43f. 5. Wilson, Andrew. Polity of a Pond (essay). Humboldt Lib. of Sc., No. 88--reprint, dated 1888. 6. Hollingworth, L.S. Variability as Related to Sex Differences in Achievement. Am. Jour, of Sociol., XIX., 1914, pp. 510-530. 7. Lowie, R.H. & Hollingworth, L.S. Science and Feminism. Sci. Mthly., Sept., 1916, pp. 277-284. 8. Montague, Helen & Hollingworth, L.S. Comparative Variability of the Sexes at Birth. Am. J. of Sociol. XX, 335-70. 1915. 9. Morgan, T.H. A Critique of the Theory of Evolution. N.Y., 1916, pp. 1-27. 10. Loeb, Jacques. Artificial Parthenogenesis and Fertilization. Chicago, 1913, pp. 3, 51f., 240f, 303. 11. Conklin, E.G. Organ-Forming Substances in the Eggs of Ascidians. U. of Pa. Contrib. from the Zool. Lab. Vol. 12. 1905, pp. 205-230. 12. Loeb, J. The Organism as a Whole. N.Y., 1916, pp. 138f, 151-2. 13. Guyer, M.F. Being Well-Born. Indianapolis, 1916, p. 51. 14. Tower, W.L. (et al.). Heredity and Eugenics. Chicago, 1912, pp. 164, 254-5. 15. Conklin, E.G. Share of Egg and Sperm in Heredity. Proc. Nat. Acad. of Sc., Feb., 1917. 16. Goodale, H.D. A Feminized Cockerel. Jour. Exp. Zool. Vol. 20, pp. 421-8. 17. Ward, Lester F. Pure Sociology. N.Y., 1903, pp. 322f. 18. Ellis, Havelock. Man and Woman, 4th Ed. London, 1904. Ch. XVI. 19. Hall, G. Stanley. Adolescence. N.Y., 1907. Vol. II, pp. 561-2. 20. Morgan, T.H. Heredity and Sex. N.Y., 1913, pp. 155f. 21. Lillie, F.R. Theory of the Free Martin. Science, n.s., Vol. XLIII, pp. 611-13. 22. Neugebauer, F.L. Hermaphrodismus, Leipzig, 1908. 23. Vincent, S. Internal Secretions and the Ductless Glands. London, 1912, p. 69. 24. Marshall, F.H. Physiology of Reproduction. London, 1910, p. 314. CHAPTER III SEX AND SEX DIFFERENCES AS QUANTITATIVE 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.