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JOURNAL OF MAMMALOGY 
Australian marsupials of both divisions than with the Didelphidae. 
There are also certain special resemblances to the Peramelidse (Osgood, 
p. 150) which, taken in connection with other evidence, leads Doctor 
Osgood to place the csenolestids next to that family. 
IV. HABITUS AND HERITAGE OF THE REPRODUCTIVE SYSTEM 
With regard to the male generative organs of Ccenolestes Doctor 
Osgood states (p. 65) that the most noteworthy features are the extra- 
ordinary size of the prostate and Cowper^s glands, the very deeply 
cleft glans penis and the absence or great reduction of the levator penis 
muscle. The bifid glans penis occurs in both polyprotodonts and 
diprotodonts, and affords no definite evidence of relationship, and the 
other features also are difficult to interpret. 
From the comparative standpoint the female reproductive organs, 
Doctor Osgood concludes, are more significant than those of the male. 
They are distinctly of a diprotodont rather than a polyprotodont type. 
This is evidenced by the deep median vaginae and the long lateral 
vaginae, and Doctor Osgood concludes that so far as gross examination 
indicates, parturition may take place by a short cut through asecondaril}^ 
developed direct median passage, as in Perameles and the Macropodidae. 
The accessory reproductive characters of the female also afford some 
slight evidence of relationship with Australian forms, since there are 
four mammae, as in many Australian genera, in contrast with the much 
higher number (up to twenty-seven) in the Didelphidae. But the 
excessively high birth rate may be one of the features to which the 
Didelphidae owe their survival, and it may therefore be a specialization 
in that family. On the whole, in the characters of the reproductive 
system Ccenolestes shows a closer resemblance with Australian than 
with known Holarctic forms. 
In conclusion, although the zoogeographic bearings of these facts 
have already been carefully considered by Doctor Osgood, it is to be 
hoped that he and other specially qualified authorities will further 
develop the true significance of these Australian-like characters in a 
South American family. 
American Museum of Natural History, New York City, 
