THE COMMON AMERICAN OPOSSUM 



(Didelphys virginianus) 



THE familiar 'Possum of American natural history and folk-lore enjoys 

 the distinction of being the only Marsupial found in the northern 

 part of the world, and thus it was the first of these pouched beasts 

 to come under the notice of naturalists. 



Although considerably the largest of its family (Didelphyidce), it 

 is not a very big animal, hardly equalling an ordinary Cat in size ; 

 and in general structure it is a good type of the American Opossums, 

 which are a very uniform group in most respects. 



Its short legs have five toes on each foot, all clawed with the 

 exception of the great toe of the hind-feet, which can be opposed to 

 the others like a thumb, so as to aid in climbing. The teeth much 

 resemble those of the true Carnivora in general appearance, the canines 

 being large, the molars sharp, and the incisors insignificantly small. 

 The incisors, however, are more numerous than in the Carnivora proper, 

 which never have more than six in each jaw, whereas the Opossum's 

 incisors are ten in number in the upper and eight in the lower jaw; 

 their size is, however, so small that they cannot be of very much use 

 to the animal. 



The tail is only hairy at the root, being bare and scaly like a Rat's 

 for the rest of its length, and it is strongly prehensile, so that the 

 animal can suspend itself by it when it wishes to lower itself down to 

 reach something from a higher bough when foraging for food in a tree. 



The ragged-looking coat varies a good deal in colour, not only 

 locally, but individually and as a matter of age; in the mixture of 

 black and white hairs it presents the darker colour predominates in 

 the younger specimens, and the light in the older ones. 



This Opossum has much the widest range of its family, being, in 

 fact, a member of a tropical group which has intruded, or succeeded 

 in maintaining itself, in a temperate region, much like the Kingfisher 

 among our British birds ; for it is not confined to North America, but 

 ranges through Central America down through Brazil, the so-called Crab- 

 eating Opossum of South America not being a really distinct species. 



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