SEX BIOLOGY AND PSYCHOLOGY 141 



secretory mechanism of the reproductive organs : but 

 his life is not subordinated to it in such an iron-bound 

 way. To start with, he has gradually lost all semblance 

 of a breeding-season. Traces of it survive in some 

 primitive races, but in civilized communities all one 

 can say is that the number of births may show a 

 slight seasonal variation ; and the reproductive organs 

 are capable of function in all twelve months of the 

 year — a. state of affairs known, I believe, in no other 

 vertebrate or at least in no wild species. ^ 



In the second place, there has been in the female a 

 further emancipation of the sexual life. In all other 

 mammals the female will only receive the male at 

 certain well-defined periods, which in their turn depend 

 on cyclical changes in the ovaries. In man this restric- 

 tion has been overcome, and, in spite of the survival 

 of a certain degree of cyclical change in feeling, neither 

 sex is restricted any longer to certain physically- 

 determined periods for the consummation of its sexual 

 life. This is, we may say, a triumph of mind over 

 matter in the human organism, of the mental elements 

 of the sexual life over the purely physical elements. 



This is not to deny that the sexual life of man is 

 dependent upon the reproductive hormones. It is 

 apparently necessary for proper activation of the 

 sexual centres in the brain that there should occur a 

 continuous liberation of secretion from the repro- 

 ductive organs into the blood. Again, the mental 

 1 See Carr-Saunders, '22, ch. v., and M. Stopes. 



