1436 



THE POUCHED MAMMALS, OR MARSUPIALS 



corresponding to the permanent premolar of the rat kangaroos (see the figure on 

 p. 1408). Such other teeth as remain were small, and of no functional import- 

 ance. The skull is unique among Marsupials in that the sockets of the eyes are 

 completely surrounded by bone. 



This huge phalanger received its technical names on the supposition that it 

 was of purely carnivorous habits; but from the resemblance of its dentition to that 

 of the existing members of the family, it seems more probable that its diet was 

 mainly of a vegetable nature. 



THE WOMBATS 



Family PHASCOLOMTID^ 



The wombats of Australia and Tasmania, w r here they are represented by three 

 existing species all referable to the one genus Phascolomys, constitute the last family 

 of the herbivorous Marsupials. These animals are of considerable size, and charac- 

 terized externally by their massive build, short and flattened heads, broad flat backs, 

 and extremely-short and thick legs; their hind-feet being plantigrade. Their ears 

 are small or of moderate size, and more or less pointed; the eyes are small, and the 

 tail is reduced to a mere stump. The fore-feet have five toes, of which the first and 

 fifth are considerably shorter than the remaining three, all being furnished with 

 powerful and somewhat curved nails. In the hind-feet the inner or "great " toe re- 

 sembles that of the phalangers in being unprovided with a nail, although it cannot 

 be opposed to the rest; the others have strong, curved nails and are of nearly equal 

 length, but the second and third are relatively slender and partially united by skin, 

 thus foreshadowing the " syndactylism " of the two foregoing families. The most 

 distinctive feature of the wombats is, however, their dentition. The teeth, twenty- 

 four in number, all grow uninterruptedly throughout life, and thus never develop 

 roots. The incisors are reduced to a single pair in each jaw, these being exceedingly- 

 powerful chisel-shaped teeth, 

 with enamel only on their front 

 surfaces, thus resembling the in- 

 cisors of Rodents. The cheek- 

 teeth are five on each side, of 

 which the first is a premolar, 

 and separated by a long interval 

 from the incisor. Each molar 

 is much curved, and consists of 

 two triangular prisms; but the 

 premolar comprises but one such 



prism. It will thus be evident that, so far as their teeth are concerned, the wom- 

 bats simulate the Rodents, to many of which they also approximate in habits. In 

 general appearance these Marsupials are, however, curiously like diminutive bears, 

 as shown in the illustration on p. 1438. 



Of the three species of the genus, the smallest is the Tasmanian wombat (P. 

 ursinus) , inhabiting Tasmania and the islands in Bass Strait. It is characterized by 



SKELETON OF WOMBAT. 



