0,71, 



FIG. 162. Diagrams, illustratin the development Jof the urinogenital organs of 



the Craniata. 



A, pronephros and its duct. B, atrophy of pronephros, development of meso- 

 nephros ; C, differentiation of Wolffian and Miillerian ducts ; D, development of 

 metanephros, male type ; E, female type. 



al. bl. allantoic bladder ; an. anus ; cl. cloaca ; gon. gonad ; int. intestine ; m.c. 

 Malpighian capsule ; ms. n. d. mesonephric (Wolffian) duct ; ms. nph. meso- 

 PRACT. ZOOL. Q Q 



