112 



MORPHOLOGICAL TYPES 



mc. 



#S58fc /■ 



Fig. 53. — Method of formation of the kidneys in amniotes. 



A, larval condition, with Mullerian duct (Md), Wolffian duct (Wd), 

 mesonephric funnels (mi) opening into the splanchnocoel (sc) ; i, intestine. 

 The ureter (u) arises from the base of the Wolffian duct and divides into a 

 number of tubes which eventually connect with the metanephric capsules 

 (mc). B, condition in the adult male. The Mullerian duct has disappeared 

 and the Wolffian duct persists as the vas deferens (vd), receiving the sperms 

 from the testis (t) by means of the vasa efferentia (ve). The ureter drains 

 the urine from the metanephros (m) to the bladder (b). C, condition in the 

 adult female. The Mullerian duct persists as the oviduct (od), the opening 

 of which into the splanchnocoel is the Fallopian tube (Ft) ; o, ovary. The 

 Wolffian duct has disappeared. 



