HERMAPHRODITISM. 6 1 



day, — the designation, sexual neutrality, or indifference, is inappro- 

 priate, since the ' ' cortical ovules ' ' of the germinal epithelium have 

 from the first the precise morphological significance of female elements 

 or ova. In the female, they proceed by multiplication to form the 

 ovary; in the male, they degenerate. (2) The period of hermaph- 

 roditism begins with the seventh day. In the male, the male ovules, 

 from which the sperms are afterwards developed, appear in the central 

 tissue; but at the same time cortical or female ovules may be seen 

 persisting. Similarly, in the developing ovary of the female, the 

 central or medullary portion, strictly separated by a partition of con- 

 nective tissues from the egg-forming layer, contains a large number 

 of medullary or male ovules. (3) This hermaphroditism is of short 

 duration. The cortical or female ovules disappear from the testes by 

 the eighth or ninth day; and the medullary or male ovules have by 

 the tenth day disappeared from the ovary. In regard to mammals, 

 Laulani6 affirms, allowing some peculiarities, that the same three 

 stages of germiparity, hermaphroditism, and unisexuality occur. 



Ploss has already been referred to as another investigater who 

 maintains the existence of embryonic hermaphroditism. Such also 

 is the view ,held by Professor Sutton, who concludes that both sets 

 of organs are equally developed up to a definite period, and empha- 

 sizes the consequent necessity for the hypertrophy of one sexual 

 rudiment over the other. Only thus can unisexuality be established. 

 It ought, perhaps, to be noted that hypertrophy is hardly a term 

 strictly applicable to predominance of male over female organs, 

 since, in our contention, the whole nature of male organs or elements 

 is the physiological reverse of abundant nutrition. 



III. Casual or Abnormal Hermaphroditism. —In many species 

 which are normally unisexual, a casual hermaphrodite form occasionally 

 presents itself. The embryonic equilibrium or bisexuality — one of 

 the two must in a variable degree exist — is retained as an abnormality 

 into adult life. Even as far up in the organic series as birds and 

 mammals, such casual and yet true hermaphrodites occur. In most 

 cases, at least, the result is sterility. Among amphibians, which 

 abound in reproductive peculiarities, hermaphroditism exceptionally 

 occurs, apart from the one case (see below) where it is known to be 

 constant. The common frog, so much dissected in our laboratories, 

 has supplied several good illustrations. Thus Marshall notes that 

 the testes may be associated with genuine ova, or an ovary may occur 

 on one side and a testis with an anterior ovarian portion upon the 

 other. Bourne gives a case of a frog with the ovary well developed 

 on the right side, and opposite this an ovary anteriorly replaced by 

 testis. One of the toads {Pelobaks fuscus) seems to be frequently 



