As I have before remarked, in all animals there are certain relics of bisexuality which never wholly disappear. The hen retains the rudimentary spurs of the cock; the useless nipple of the man develops, under certain conditions, into the lactiferous breast of the woman; in the female clitoris we see the rudimentary male penis; while in the various works on teratology may be found more or less striking evidences to support Letamendi's theory of "panhermaphrodism,"1 as a principle as universal as sex differentiation itself.

But if there be an indeterminate point at which, by absolutely unknown processes, whether fortuitous or designed, this sex separation begins, until we arrive at some more definite knowledge of that starting-point, and the morphological influences of which it is the center, we must be content to regard these subtle sex-approximations, and deviations, as, if not accidental, at least wholly beyond the domain of present knowledge. Before we class the minute organic variations from a given type as abnormalities, however, we should have a distinct idea of what constitutes an abnormality. Is the study of nosology wholly distinct from that of teratology? And how far are we justified in associating phenomena, which have been known to result from disease, with those which are equally well known to be the product of organic predisposition?

We know color-blindness and criminality to be entirely distinct, as diseases, from scarlatina and smallpox; but where does the difference begin as to symptomatology? And if Letamendi's suggested theory1 of latent male germs in the female, and female germs in the male, striving for mastery, and thus producing sexual inversion, be true, is it not equally true that the same, or similar, embryological action is what produces the normal sex?

So far as the psychic features of inversion are concerned, it is quite probable that they depend largely if not wholly on antenatal influences; but those influences, notwithstanding all that has been written, are still too problematical and vague to constitute little more than what Moll calls mere "happy thoughts" in the morphology of the subject,

While it may be regarded as settled, therefore, that sexual inversion is a product of degeneration, psychical and physical, toward the full development of which a great many causes contribute; while it is a phenomenon, in the main, of weakened will power, licentious habits of thought, and a too luxurious civilization; while it springs from a false sexual ideal, rather than deficient intellect; and while its practice is so destructive of both social and private morals that the law takes almost universal cognizance of it, yet, in the nearly total absence of what may be regarded as adequate scientific data concerning its nature and causation, I deem it prudent to touch only very lightly upon the vast mass of speculation, physiological and psychical, which recent years have produced in reference to it; limiting myself to those practical phases of the question in which society suffers from, and endeavors to protect itself against, the sexual invert; and, without assuming that high moral tone which would be distinctly out of place in dealing with a pathological problem, to protect the invert himself, or herself, from physical destruction, by pointing out the penalties which this, in common with every other violation of natural law, must ultimately entail.

But, before entering in detail upon the various phases which the pathology of the theme presents, a brief synopsis of the views currently held in scientific circles, and sanctioned by writers of unquestioned repute, appears to be at least proper.