ACTION OF SEX HORMONES IN FOETAL LIFE 



433 



Fig. 11 Normal male 15.8 cm. long. X '. From two-sexed pair 6 collected 

 March 4, 1915. Chorion was single, constricted between the two foetuses. The 

 long gubernacula have grown into the groin but have not yet entered the scrotal 

 sacs. The testes are still in the bodj- cavity, though close to the entrance to the 

 saccus vaginalis. The left testis, posterior in position to the right, corre- 

 sponding to the more posterior location of the left kidney. The seminal vesicles 

 are well formed with distal buds. The urinogenital system of the free-martin 

 twin is shown in figure 16. 1, spermatic artery; 2, testis; 3, Wolffian duct (vas 

 deferens); 4, vesiculae seminales; 5, gubernaciilum ; 6, urinogenital sinus; 7, root 

 of penis; 8, rectum; 9, umbilical artery; 10, ureter; 11, allantois. 



