372 INTERNAL SECRETION 



showed to be an alveolar carcinoma, the pubertic symptoms 

 gradually disappeared, and the boy became mentally and physic- 

 ally the same as other boys of the same age. In this case the 

 connection between the premature signs of puberty and the 

 pathological hypergenitalism is abundantly clear. 



Before passing to a consideration of the influence which cas- 

 tration has upon the secondary sex characteristics, it is expedient 

 first to consider the significance of that organ which is regarded 

 as the pronounced characteristic of the female sex, but which has 

 no recognizable relationship to the function of reproduction, 

 namely, the mammary gland. This gland is present in the 

 embryonal beginnings of both sexes; in new-born infants it is 

 confined to a few ducts in the neighbourhood of the nipple, which 

 may produce a transient secretion known as " witches' milk ' 

 (Hexenmilch). 



A remarkable development of the mammary gland takes 

 place in female individuals at the period of puberty, though this 

 increase in size is largely the result of the deposition of fat. The 

 enlargement during puberty of the mammae of boys is probably 

 entirely due to fatty deposition ; and gynaecomastia that is, 

 abnormal development of the mammae in males is probably due, 

 in many instances, to testicular hypoplasia, or to atrophy of the 

 testicles as the result of pathological processes. Males which 

 show abnormal development of the adipose tissue at certain points 

 of predilection, are to be regarded as eunuchs or semi-eunuchs. An 

 extremely instructive instance of such pseudo-gynaecomastia is 

 described by Foges. 



As far as the female mammary gland is concerned, there is 

 no doubt that its development at the period of puberty is 

 influenced by the genital gland. It has been proved experiment- 

 ally that the mammary gland does not develop in animals which 

 have been castrated in early youth ; while normal development 

 takes place after ovarian transplantation. That the influential 

 factor is supplied by the ovaries and not, as the simultaneous 

 uterine atrophy suggests, by the uterus, has been proved by 

 experiment (Foges). 



The periodical swelling of the mammas observed in many 

 women during menstruation, and the occurrence of similar 

 phenomena in animals during the rutting period, are undoubtedly 

 attributable to the internal secretory activity of the ovaries. 



The most important changes in the mammae are those which 

 take place during pregnancy. At the commencement of this 

 state, what must be regarded as a true hypertrophy takes place, 

 which continues until parturition. 



There was at one time an all-prevailing view that the mam- 

 mary hypertrophy of pregnancy was the result of communication, 

 effected by way of the nervous system, between the mammary 

 planet and the pregnant uterus ; this theory has, however, long 



