THE MALE HORMONE 



Seminal dact- 

 drawn out 



Tu-bea coiled 

 in place 



Fio. 31. Arrangement of the tubules of the testis, the epididymis, and 

 the seminal duct. Adapted from Spalteholz and Huber. From Attaining 

 Manhood, by George W. Corner, by courtesy of Harper anl Brothers. 



the seasons of inactivity spermatogenesis ceases and the 

 testis diminishes in size. 



The testis, like the ovary, is under control of the pituitary 

 gonadotrophic hormones. One of the most striking results 

 of the brilliant campaign of investigation of the pituitary 



{ m } 



