masculine form and soul, he has them from another sterol, scarcely different from the first. The sexualizing secretions which condition the differentiation of the sexes affect equally the instincts, tendencies, and desires. In impregnating the nervous system, these two chemical forces color minds and souls. 'So that where the testosterone controls, attraction will be strongly felt for the forms which the folliculin has modelled. (Jean Rostand, loc. cit., p. 59)

In their laboratories the biologists bring about strange experiences. One reverses the sex of a pullet by introducing a chemical substance into the embryo. Another establishes that male to ads, if they are castrated at an early age, may be changed into females, develop true ovaries and lay fertile eggs which produce tadpoles, children of two fathers. Another, a third, brings about in the capon the development and swelling of the comb, the ability to crow, and the belligerent disposition with the testicular fluid of the bull or the bear. 'One affirms that animals castrated before sexual maturity do not have the sexual instinct; but that rabbits with the gonads removed and submitted to injections of propionate of testosterone become capable of coupling, (Daval and Guillemain, Psychology I, p. 433)

Crew has indicated the case of a hen, and Riddle that of a female pigeon, which, following a tubercular infection, acquired the male sex. 'Nothing prevents one from supposing that in the human species as well an in.dividual can acquire in the course of his development and under the influence of exceptional conditions the opposite sex from that for which he was designed by his chromosomes.' (Jean Rostand, From the Fly to Man, P. 121)

In submitting an organmsm to the combined action of masculinizing and feminizing substances, one is obliged to realize the characteristics proper to the two sexes. 'By a castration followed by a double grafting, ovarian and testicular, one succeeds in producing bi-sexual individuals. There is no neutralization of the masculinizing effect but rather a superposition of the two effects. The animals carrying an ovary and a testicle do not take a single aspect nor do they adopt a form of behavior intermediary between the masculine and the feminine; they exhibit the traits and instincts of both sexes. Sometimes an alternating of masculine and feminine phases can be observed under the influence of the double chemical application.' (Jean Fostand, loc. cit., p. 123-130)

Every organism contains the potentiality of realizing the characteristics appropriate to both sexes. The differentiation of sex is determined by certain chemical

29