THE YAPOCK OPOSSUM. 193 



It is, therefore, rather startling to find that there 

 is a species of opossum which cannot even climb a 

 tree, which obtains its prey in the water, whose feet 

 are modified into oars, and whose tail acts as a rudder. 

 Such, however, is the Yapock Opossum, a handsome 

 creature, with a coat of light grey, blotched with great 

 bars and patches of black. All the paws are webbed, 

 but the fore paws have the web extending only as far 

 as the first joints, so that they can be used after the 

 manner of hands. This structure, however, renders 

 them incapable of being employed in traversing the 

 branches of trees, as is done by the terrestrial, or, I 

 may rather say, the arboreal opossum. Even the shape 

 of the animal is unlike that of the other opossums, and, 

 to a practised eye, at once indicates its aquatic character. 

 The toes of the hind feet are much lengthened, 

 and, as they are webbed down to the claws, they form 

 very effective instruments of propulsion. By their aid, 

 the Yapock can swim so swiftly and actively that it 

 can chase and capture even the fish in their own 

 element, and, indeed, has been captured in a fish-trap. 

 The animal dived into the trap in pursuit of the fish, 

 and, being unable to extricate itself, was drowned. 



Aquatic insects, Crustacea, and similar creatures, 

 form part of the Yapock' s food. Perhaps the nature 

 of its food may have some connection with the curious 

 fact that the mouth is furnished with cheek-pouches, 

 like those of the monkeys. These pouches are very 

 large, extending completely along the side of the head, 

 and are supposed to be given to the animal for the 

 purpose of enabling it to gather a store of water- 

 insects, and to take them home to its young. 



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