146 ESSAYS OF A BIOLOGIST 



phase of the matter is being investigated by many 

 workers to-day ; provisionally we may say that 

 pituitary and adrenal cortex are especially concerned. 

 In the second place the gonads, once activated and 

 in normal working order, react upon the other duct- 

 less glands. It thus comes about that the relative 

 proportion or relative activity of the parts of the 

 whole ductless gland system is different in male and 

 female. Blair Bell is the protagonist of this view. 

 A woman is a woman, he says, not merely because 

 of her ovaries, but because of all her internal secre- 

 tions, of her endocrine balance as a whole. 



It cannot be said that we have any certainty on the 

 details of this subject. It is clear, however, that 

 some such fundamental difference does exist, and it is 

 therefore further probable that if a woman has a 

 thyroid, say, or an adrenal which for some reason 

 (and there are many possible reasons) is producing 

 an amount of secretion abnormal for a woman but 

 more like that which is produced by a man, she will, 

 in spite of her ovaries, be more masculine in tendency. 



I will content myself with one example. The 

 cortex of the adrenal gland, if active beyond a certain 

 measure, assists the development of male, prevents 

 the development of female, characters. Women 

 with adrenal tumours frequently develop moustache 

 and beard and other appanages of the male. One 

 presumes that a slight preponderance of the adrenal 

 cortex in the normal endocrine make-up will lead 



