... secretions and the sex complex. The male and the female type of body. How removal of sex glands affects body type. Sex determination. Share of the egg and sperm in inheritance. The nature of sex—sexual selection of little importance. The four main types of secretory systems. Sex and sex instincts of rats modified by surgery. Dual basis for sex. Opposite sex basis in every individual. The Free-Martin cattle. Partial reversal ... — Taboo and Genetics • Melvin Moses Knight, Iva Lowther Peters, and Phyllis Mary Blanchard