i 
377 
novemcinctus but in that of Tragulus as well, since he has recently 
observed that such an elongation undoubtedly takes place in Didel- 
phys marsupialis, in which a type of postcava (Fig. 5) is occasionally 
met with in the adult similar to that found in Tragulus (Fig. 2) 
and Dasypus novemcinctus [Fig. 4%)]. 
V, renalis dext. 
V,renalis sinist. 2 
V. rena- 
lis dext. - V. renalis sinistra 
Kidney 
A. spermatica ant. 
A. spermatica 
A. mesenteriea post. V.sper- 
matica V. spermatica 
Aorta A. spermatica post. 
Posteaya 
V. spermatica 
Aorta 
Y. spermatica 
A. iliaca ext. VY. iliaca ext. 
V. iliaca ext.. A. iliaca ext. 
A. iliaca int. 
VY. iliaca int. : 
VY. iliaca int. 
A. iliaea int. 
Fig. 4: 
Fig. 4. Postrenal division of the postcava of Dasypus novemeinetus. After HOCH- 
STETTER. Adult. Ventral view. 
Fig. 5. Postrenal division of a double or bifurcated posteava of Didelphys mar- 
supialis (L.). Type II. Adult. Ventral view. 
IPT 15), 
The common iliac veins (paired portion of postcava) in Tragulus 
undoubtedly represent either persistent postcardinal veins, or veins 
which have been derived from the postcardinals in correlation with 
the migration of the permanent kidneys and the degeneration of the 
mesonephroi. 
1) C. F. W. McCuvre, A Contribution to the Anatomy and Deve- 
lopment of the Venous System of Didelphys marsupialis (L.). Part I, 
Anatomy. American Journal of Anatomy, Vol. 2, 1903 (see Fig. 8, 
Plate II). Part II, Development. American Journal of Anatomy, Vol. 5, 
1906 (see p. 197). 
