SECONDARY CHARACTERISTICS 17 



first stage extends from birth until puberty. During stages of 

 this period the development of sex-characteristics is of secondary 

 slow : in the girl the mind is often not pronouncedly character- 

 feminine, although girls are supposed to, and sometimes 

 do, show a marked liking for dolls and sewing, in con- 

 tradistinction to the preference of boys for balls and 

 fighting. So, too, in girlhood the special characteristics 

 of mammary development and plumpness are usually 

 absent, and the genital functions are dormant. At 

 puberty, however, there is a remarkable change, which 

 is not only physical but also psychical. Normally, at 

 this epoch a girl becomes shy, reserved, and essentially 

 feminine in her pleasures and in her relations with men. 



We must now briefly consider the influence the influence of 

 ductless glands exercise upon the pubescent develop- gj^nfaon 

 ment of the female genital organs and their functions, pubescent 



° ... development 



and upon the secondary characteristics in the normal of reproduct- 

 woman. This part of the subject is one which, in its lve organs * 

 pathological aspect, constantly confronts us in our 

 clinical work. 



Although the genitalia may be normal morphologic- 

 ally at birth (fcetal development), yet, as indicated 

 already, they only become functionally active at puberty 

 (complete development) if the whole hormonopoietic 

 system is in perfect harmony, and is acting efficiently 

 and normally in regard to its sexual functions. Thus, 

 thyroid or pituitary insufficiency may cause the genital 

 organs to remain infantile ; and we shall see later that 

 disease of these structures may cause retrogression in 

 the genitalia even after they have functionated normally. 

 Further, it is believed that the gonads and uterus remain 

 not fully developed until the thymus atrophies at the 

 time of puberty 1 . At this period of life, owing to 

 the withdrawal of the thymus secretion, as some think, 

 the genital organs begin to develop ; other investigators, 

 however, believe that it is the development of the 



1 Compare p. 83 for discussion concerning the question of the 

 status of the thymus in regard to internal secretion. The statements 

 in this place are illustrations only. 



2 



