THE OPOSSUMS. 



DIDELPHID^. 



The term Opossum has been applied indiscriminately 

 to the species of Marsupial animals ; but, by the 

 same rule that we use the words dog, cat, weasel, 

 &c., to distinguish the different genera of carnivor- 

 ous Mammalia, so ought we to express differences of 

 the same kind, by using restricted English names for 

 the different genera of the Marsupiata, which are 

 quite as easily distinguished as those just mentioned. 

 The term Opossum, therefore, is here restricted to 

 that group which was first known by the name, con- 

 stituting the genus Didelphys, the species of which 

 (unless in a fossil state) are only found in the New 

 World ; that is, in the more southern portions of 

 North America, and in the whole of South America. 

 The figures given in the body of this work, will 

 convey a more accurate idea of the general form and 

 appearance of these animals, than words can do, — 

 some of the smaller species might, by the common 

 observer, be mistaken for rats and mice, were it not 

 for the elongated and pointed muzzle ; others again, 

 greatly resemble shrews — the largest known species 

 are scarcely equal to the common cat in size. 



