A C 





- ^"''X'V 





3*&V3 



Fig. 2. A, D and F illustrate normal foetal development of the seminal 

 vesicles: B, C, E and G were explanted at 17+ days and were cultured for 

 2 days (B) or 4 days (C, E, G). A: normal foetus at 17+ days with Wolffian 

 duct dilatations and medial Mullerian ducts. B: 19+ day-old explant with 

 testes, showing Wolffian duct dilatations and medial utriculus prostaticus. 

 C : 21 + day-old explant without testes ; the Wolffian ducts have retrogressed 

 and no seminal vesicles have developed. D: normal foetus at 19+ days; the 

 large seminal vesicles are near their junction with the corresponding ductus 

 deferens. E: 21+ day-old explant with no testes but with testosterone; 

 ejaculatory duct on the left, ductus deferens and seminal vesicle on the right. 

 F : normal foetus at 21 + days ; length of the seminal vesicles 1 • 1 mm. G : 21 + 

 day-old explant with testes; length of the seminal vesicles 16 mm. ( X 90). 



facing page 8 



