/T. TodcL 'd5 



Fig. 9. — The action of pituitary gonadotropic hormone on the urogenital tract of the female 

 chick embryo. (From Domm and Dennis, Proc. Soc. Exp. Biol. Med., 36, 766-69 [1937].) 



Lejt: control; right: treated embryo which received 5 rat-units of sheep pituitary extract for 

 5 days (fifth to ninth day of incubation); incubation of both embryos continued until the 

 eighteenth day. rr: right rudimentary gonad; lo: left ovary; wb: Wolffian body; wd: Wolffian 

 duct; Im: left Miillerian duct; rm: remnant of right Miillerian duct; a: adrenal; c: cloaca; 

 m: kidney; u: ureter. 



