TESTICLE AS GLAXD OF INTERNAL SECRETION 523 



Puberty is determined when the internal secretion of testicle reaches 

 a certain predetermined amount. This can be accelerated as to time by 

 excess function or an increase in number of normally functioning inter- 

 stitial cells. It is possible to do homo and auto transplantation of the tes- 

 ticle with fair success as regards the preservation of the structures produc- 

 ing the internal secretion. As regards the preservation of the spermato- 

 genic structures, I have been successful in chickens, others have been 

 successful in frogs. In mammals and humans there has been less suc- 

 cess. The administration of fresh or dried testicle, adrenal gland and 

 pituitary gland will stimulate both sexual libido and spermatogenesis. 



