INTERSEXUALITY 367 



and of Steinach with ligation of the vas or with transplantation. 

 But the fact remains that notwithstanding the extraordinary 

 degenerative changes which take place in the generative part 

 of the ovarian or testicular graft the latter is still able to 

 change the sex characters to a certain degree in the direction 

 of the sex of the graft. 



On the other hand, many objections to Steinach's theory 

 have been urged by pathologists. These will be discussed below. 



C. INTERSEXUALITY IN MAN, MAMMALS, 

 AMPHIBIANS AND INSECTS. 



Intersexuality is very widespread in birds, mammals and 

 man. There is an enormous variability in regard to the somatic 

 and psychical characters of intersexual individuals. There is 

 also great variability in the time at which the individual 

 becomes intersexual. 



We shall deal in the following sections with such cases only 

 as serve to elucidate the morphogenetic basis of intersexuality. 

 Our main problem will be the following : how far is any abnormal 

 condition of the endocrine function of the sexual gland or of 

 some other internall}^ secreting gland involved in intersexu- 

 ality? 



I. Man. 



{a) Homosexuality. 



According to clinical observations there are many cases of 

 homosexuality where there is a periodic change in the psycho- 

 sexual behaviour. This periodicity relates to men as much as 

 to women. Sometimes even changes in the condition of the 

 somatic sex characters may take place. Steinach is inclined 

 to consider these periodic changes as analogous to those 

 observed in experimental hermaphroditism. One might suppose 

 that in such individuals there is an hermaphrodite gland and 

 a periodic change in the quantities of male and female sexual 

 hormones produced. Examining the testicles of homosexual 

 individuals, Steinach (1919 c, 1920 b) found that the inter- 

 stitial tissue contained large epithelioid cells, not resembling 

 the ordinary male interstitial cells of the testicle, but rather 

 like the luteal cells of the ovary. Steinach is inclined to ascribe 

 homosexuality to female sexual hormones produced by these 

 cells. As long as the male sexual hormones quantitatively 



