Charles F. W. McClure 389 
so far craniad, is the usual method in the wombat can only be deter- 
mined through further investigation. At any rate in Didelphys and other 
marsupials thus far examined, including the wombat (Hochstetter, 93), 
the internal spermatic veins open into the, postcava at about the same 
level as that figured for Petrogale. 
In the wombat the renal and spermatic veins anastomose with each 
other, on both sides, by means of a vessel which follows the ureter.“ In 
Didelphys a similar anastomosis was met with, and in well injected ani- 
mals the anastomotic vessel could be distinctly traced caudad of the 
spermatic veins as far as the neck of the bladder. Hochstetter, 93, with 
the exception of its extension to the bladder, was the first to observe the 
presence of this anastomosis in marsupials. He has also figured the 
same as occurring in an edentate, Dasypus novemcinctus (93, Taf. 23, 
Fig. 25). 
The above description of the postcaval vein in Petrogale and Phas- 
colomys, with the possible exception of the spermatic veins, agrees in all 
essential details with the findings of Hochstetter and others who have 
examined this vein in a number of marsupials. 
Following is a list of marsupials, known to the writer, in which the 
postrenal division of the postcava has been described, and in which it has 
been found to be similar in all respects to that of Petrogale: 
Family—Macropopip. 
Halmaturus giganteus (OWEN and HocusteEttTeER) ; Halmaturus bennetti aud 
Hypsiprymnus (spec.?) (HOCHSTETTER); Macropus rufus (WINDLE and 
Parsons) and Petrogale penicillata (WINDLE and PARSONS). ° 
Family—PHALANGERID#. 
Phascolomys wombat (OWEN and HocusTETTER); Phalangista vulpina, Bel- 
ideus ariel and Cuscus (HOCHSTETTER). 
Family—DasyuRID&. 
Phascogale penicillata (HOCHSTETTER). 
Family—DIDELPHYID2. 
Didelphys lanigera and Didelphys pusilla (HOCHSTETTER). 
From what has been stated above it is evident that the postcaval vein 
is formed in a variety of marsupials in a definite and uniform manner 
and that its variations when occurring represent, as in other mammals, 
exceptions to the general rule. In Didelphys marsupialis, however, the 
lt This anastomosis is undoubtedly present in Petrogule; the vessels, however, were 
not injected in the animal examined by the writer. 
