be afforded by the psychical phenomenon of sexual perversion and inversion.”  Similarly in a case of unilateral secondary male character in an otherwise female pheasant, C.J.  Bond has more recently shown (Section of Zooelogy, Birmingham Meeting of British Medical Association, British Medical Journal, Sept. 20, 1913) that an ovi-testis was present, with degenerating ovarian tissue and developing testicular tissue, and such islands of actively growing male tissue can frequently be found, he states, in the degenerating ovaries of female birds which have put forth male plumage.  Sir John Bland-Sutton, referring to the fact that the external conformation of the body affords no positive certainty as to the nature of the internal sexual glands, adds (British Medical Journal, Oct. 30, 1909):  “It is a fair presumption that some examples of sexual frigidity and sex perversion may be explained by the possibility that the individuals concerned may possess sexual glands opposite in character to those indicated by the external configuration of their bodies.”  Looking at the matter more broadly and fundamentally in its normal aspects, Heape declares (Proceedings of the Cambridge Philosophical Society, vol. xiv, part ii, 1907) that “there is no such thing as a pure male or female animal, but that all contain a dominant and recessive sex, except those hermaphrodites in which both sexes are equally represented....  There seems to me ample evidence for the conclusion that there is no such thing as a pure male or female.”  F.H.A.  Marshall, again, in his standard manual, The Physiology of Reproduction (1910, p. 655 et seq.), is inclined to accept the same view.  “If it be true,” he remarks, “that all individuals are potentially bisexual and that changed circumstances, leading to a changed metabolism, may, in exceptional circumstances, even in adult life, cause the development of the recessive characters, it would seem extremely probable that the dominance of one set of sexual characters over the other may be determined in some cases at an early stage of development in response to a stimulus which may be either internal or external.”  So also Berry Hart ("Atypical Male and Female Sex-Ensemble,” a paper read before Edinburgh Obstetrical Society, British Medical Journal, June 20, 1914, p. 1355) regards the normal male or female as embodying a maximum of the potent organs of his or her own sex with a minimum of non-potent organs of the other sex, with secondary sex traits congruent.  Any increase in the minimum gives a diminished maximum and non-congruence of the secondary characters.

We thus see that the ancient medico-philosophic conception of organic bisexuality put forth by the Greeks as the key to the explanation of sexual inversion, after sinking out of sight for two thousand years, was revived early in the nineteenth century by two amateur philosophers who were themselves inverted (Hoessli, Ulrichs), as well as by a genuine philosopher who was not inverted