SEX BIOLOGY AND PSYCHOLOGY 147 



to a less feminine type of woman than normal. I 

 repeat that we are but on the verge of the matter and 

 that premature speculation is certainly risky and 

 probably fallacious. But all the same, there is very 

 little doubt that we are on the right track, and that 

 we shall have to search for the finer shades of tem- 

 peramental difference between man and woman 

 not so much in differences in the quality of the 

 secretion of testis or ovary as in differences of balance 

 in what the Americans call the * endocrine make-up.' ^ 

 There is, however, also the possibility of difference 

 in the quality of gonad secretion, and of recent years 

 Steinach and his followers have been claiming that 

 this may be at the bottom of many cases of so-called 

 ' perversion of sexual instinct.' The latest claim of 

 this school is that homo-sexual men may be rendered 

 hetero-sexual in instinct by removal of their testes 

 and implantation of a testis from a sexually normal 

 person — from a man, for example, who is being 

 operated on for cryptorchidism. It is frankly im- 

 possible as yet to say whether their conclusions are 

 well founded : a very much larger series of cases 

 will be necessary, and the possibility of suggestion's 

 action must be eliminated. It is well to remember, 

 however, that there is no theoretical objection to 

 the possibility. We know that in various lower 

 animals, such as moths and flies, the balance between 

 the male- and female-determining factors in the 

 1 See Vincent, '21 j Harrow, '23. 



