404 Venous System of Didelphys Marsupialis 
PLATE IJI.—TypeE III, A. 
Fig. 11. Dorsal view (f). 
Fig. 12. Dorsal view (<j). 
Fig. 13. Dorsal view of Fig. 14. 
Fie. 14. Ventral view (<). 
PLATE IV.—TyYPeE III, B. 
Fig. 15. Ventral view (9). Aa. spermaticae internae pos- 
teriores pass through a foramen in postecaya. 
Fie. 16. Ventral view (0). Aa. spermaticae internae pos- 
teriores pass through foramen in posteava. 
Fie. 17. Ventral view (0). Posteava bifurcated caudads 
of Vv. spermaticae internae. Remains of venous ring 
through which the umbilical artery passes in the embryo. 
Fie. 18. Ventral view (9). Posteava partially bifurcated 
at its caudal end. 
Fie. 19. Ventral view (<j). 
Fig. 20. Ventral view (1). Foramen in posteava through 
which the Aa. spermaticae internae posteriores pass. 
Fie. 21. Ventral view (0). Postcava bifurcated. 
Fie. 22. Ventral view (<3). 
PLATE V.—TYPE III, C. 
Fie. 23. Ventral view (,P). Postrenal division of postcava; 
also showing the two pairs of internal spermatic arteries 
(AiSsa: a. andy Aes 12 p:))- 
Fie. 24. Ventral view ((‘). 
Fig. 25. Dorsal view (\P). Posteava partially bifureated 
caudad of the Vv. spermaticae internae. 
