=Perverse Birds.= If we now turn to experiments reported by William Craig in the _Journal of Animal Behavior_, we see an apparently different process at work. Young male birds kept for a year in a cage with females and away from all males, will at mating time ignore entirely the females, and offer themselves to males in the mating position of the female. The same process is observable in females brought up with males exclusively. Imitation in this case seems to give exactly the same results which Steinach obtained thru castration and transplantation of gonads. If we now leave the physiologists and consult the psychoanalysts, Freud, Ferenczi, Stekel and Adler will show us that homosexualism can be produced by "purely" psychic factors. =Freud Rejects the Hypothesis of a Third Sex=: "Homosexual men who have started in our times an energetic action against the legal limitations of the sexual activity," Freud writes, "are fond of representing themselves, thru theoretical spokesmen, as evincing a sexual variation, which may be distinguished from the very beginning, as an intermediate stage or sex, a third sex. In other words, they maintain that they are men who are forced by organic determinants originating in the germ to find in a man the pleasure which they cannot find in a woman. As much as one would wish to subscribe to their demands, out of humane considerations, one must nevertheless exercise reserve regarding their theories which were formulated without regard for the psychic genesis of homosexuality. Psychoanalysis offers the means to fill the gap and to put to test the assertions of the homosexuals. It is true that psychoanalysis has fulfilled that task in only a small number of people, but all the investigations thus far undertaken have brought the same surprising results. "In all our male homosexuals, there was a very intense erotic attachment to a feminine person, as a rule to the mother, which was manifested in the very first period of childhood and later entirely forgotten by the individual. This attachment was produced or favored by too much love from the mother herself, but was also furthered by the retirement or absence of the father during the childhood period. Sadger emphasises the fact that the mothers of his homosexual patients were often masculine women, or women with energetic traits of character who were able to crowd out the father from the place allotted to him in the family. I have sometimes observed the same thing, but I was more impressed by those cases in which the father was absent from the beginning or disappeared early so that the boy was altogether under feminine influence." "It almost seems that the presence of a strong father would assure for the son the proper decision in the selection of his love object from the opposite sex.