to secure the maximum amount of fertilization.  “Increase and multiply” is so obviously the command of Nature that the Hebrews, with their usual insight, unhesitatingly dared to place it in the mouth of Jehovah.  But the hymen is a barrier to fertilization.  It has, however, always to be remembered that as we rise in the zooelogical scale, and as the period of gestation lengthens and the possible number of offspring is fewer, it becomes constantly more essential that fertilization shall be effective rather than easy; the fewer the progeny the more necessary it is that they shall be vigorous enough to survive.  There can be little doubt that, as one or two writers have already suggested, the hymen owes its development to the fact that its influence is on the side of effective fertilization.  It is an obstacle to the impregnation of the young female by immature, aged, or feeble males.  The hymen is thus an anatomical expression of that admiration of force which marks the female in her choice of a mate.  So regarded, it is an interesting example of the intimate manner in which sexual selection is really based on natural selection.  Sexual selection is but the translation into psychic terms of a process which has already found expression in the physical texture of the body.

It may be added that this interpretation of the biological function of the hymen is supported by the facts of its evolution.  It is unknown among the lower mammals, with whom fertilization is easy, gestation short and offspring numerous.  It only begins to appear among the higher mammals in whom reproduction is already beginning to take on the characters which become fully developed in man.  Various authors have found traces of a rudimentary hymen, not only in apes, but in elephants, horses, donkeys, bitches, bears, pigs, hyenas, and giraffes. (Hyrtl, Op. cit., vol. ii, p. 189; G. Gellhoen, “Anatomy and Development of the Hymen,” American Journal Obstetrics, August, 1904.) It is in the human species that the tendency to limitation of offspring is most marked, combined at the same time with a greater aptitude for impregnation than exists among any lower mammals.  It is here, therefore, that a physical check is of most value, and accordingly we find that in woman alone, of all animals, is the hymen fully developed.

FOOTNOTES: 

[72] “Analysis of the Sexual Impulse,” in vol. iii of these Studies.

[73] “The accomplishment of no other function,” Hyrtl remarks, “is so intimately connected with the mind and yet so independent of it.”

[74] The process is still, however, but imperfectly understood; see Art.  “Fecondation,” by Ed. Retterer, in Richet’s Dictionnaire de Physiologie, vol. vi, 1905.

[75] Thus a male foetus showing reptilian characters in sexual ducts was exhibited by Shattock at the Pathological Society of London, February 19, 1895.