182 ANIMAL LIFE PAST AND PRESENT. 



conical tooth corresponding to the tusk, or canine- 

 tooth (Fig. 54, a) of the dog. The hinder teeth, 

 moreover, have sharply pointed crowns, and are 

 adapted for a carnivorous diet. There may be as 

 many as five front (incisor) teeth on either side of 

 the upper, and four in the lower jaw ; and from this 

 large number of front teeth it has been proposed to 

 call this assembly of Marsupials the Polyprotodont 

 (numerous front teeth) group. Eemains of extinct 

 members of this group are common in the Secondary 

 rocks of North America and Europe, the lower jaw 

 represented in Fig. 54 illustrating the large number of 

 teeth so characteristic of several of these animals. 



We take, as an example of the group, the Tasmanian 

 Thylacine (Fig. 55), commonly known to the colonists 

 as the Wolf. The latter name, as well as the Latinised 

 Thylacine (Pouched Wolf), is applied to this animal 



Fia. 54. The left side of the lower jaw, with the front teeth broken off, of 

 a Secondary Marsupial. (After Marxli.) 



from its peculiarly dog-like appearance, which is 

 especially shown in the long and pointed muzzle, the 

 general contour of the body, arid the long tapering 

 tail, like that of a pointer. The Thylacine, which is 

 the largest of the Polyprotodonts, may indeed be 

 regarded as playing the part of the wolf in Tasmania, 



