446 



after uniting with each other ventral to the A. sacralis media, instead 

 of joining, as in Fig. 4, a V. iliaca externa on each side, unite with 



VU.d ^vX.HL#.wV>)^ ^'•^" ^ ^' ^^^^'J/ 7 ^"" V>-^''-^'^ ' 



Fig. 4. Ventral aspect. Adult J, Type II. 



Fig. 5. Dorsal aspect. Adult (J, Type II. 



For reference to abbreviations see unter Figs. 1 and 2. 



the V. iliaca externa sinistra, dorsal to the A. iliaca communis 

 sinistra. The dotted lines in the Figure indicate the position of this 

 artery. 



Type III. Those cases in which the A" v. iliacae in- 

 ternae unite with the Vv. iliacae externae to 

 form the V. cava posterior, both dorsal and ventral 

 to the A a. iliacae communes or both dorsal and 

 yentral to the Aorta. 

 Including the three sub-divisions, fourteen examples of this Type 

 were met with distributed among seven males and seven females. 

 Sub-Type III, A. Those cases in which the principal 

 union between the Vv. iliacae inter nae and ex- 

 ternae lies yentral to the arteries in question. 

 Four examples of this Sub-Type were met with distributed among 

 two males and two females. 



Figs. 6 and 7 represent, respectively, a ventral and dorsal view 

 of the same preparation. 



In the ventral view, Fig. 6, the V. cava posterior appears to 

 be formed in the same manner as that represented in Fig. 1, that 

 is so far as the mode of union of the large veins is concerned. In 

 the dorsal view of this preparation. Fig. 7, in addition to the above 



