﻿THE OPOSSUMS. 1 95 



tion of young born in the imperfect and helpless condition 

 characteristic of all the Marsupials, is hard indeed to divine. 

 In the case of the Opossums, the young of many species, after 

 becoming detached from the teats, are enabled to travel about 

 with her by twisting their prehensile tails round the tail of their 

 parent ; but it will be obvious that they are by no means so 

 secure or well protected as they would be m a warm and com- 

 fortable pouch. 



With the exception of the aquatic Yapock, or Water-Opossum, 

 the members of the family are mainly arboreal animals, spend- 

 ing the hours of daylight concealed among the foliage or in the 

 hollows of the trees they frequent, and only issuing forth at 

 night to procure food. A few species belonging to the sub- 

 generic group Peramys are, however, more or less terrestrial in 

 their habits ; and it is a remarkable fact that some of the nor- 

 mally arboreal species have extended their range to the open 

 pampas of Argentina, where they have from necessity been 

 forced to adopt a mode of life foreign to their nature, and 

 thus affording an instance of the pliancy and adaptability 

 of animals. Whereas the normally tenestrial species alluded 

 to above resemble the Shrews both in appearance and mode of 

 life, the majority of Opossums may be more aptly compared, 

 as regards their role in nature, with the Tree-Shrews i^Tupaia) 

 of the Oriental region and the Broad-footed Pouched Mice of 

 Australasia. 



As regards their food, the smaller species feed mainly or ex- 

 clusively on insects, which also constitute a considerable pro- 

 portion of the nutriment of the larger kinds. These latter, 

 however, also prey upon the smaller reptiles, as well as birds 

 and their eggs ; being, in fact, almost omnivorous. For the 

 capture and comminution of insect prey the sharp teeth of these 

 animals are especially adapted; the large number of cusps on the 

 molars being just the structure best suited for piercing the hard 



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