298 PHASCOLOMYS. 



GENUS PHASCOLOMYS. 



IN this genus the incisors are two in numher in 

 each jaw, and the molars are five on each side of 

 each jaw. The incisors are large and deeply era- 

 planted in their respective sockets, like those of the 

 Rodentia, (if the teeth so called in the latter animals 

 be really incisors, for this I think douhtful ;) those 

 of the upper jaw are somewhat compressed, and 

 when removed from the socket are found to he curved, 

 and hollow at the base. The worn surface of the in- 

 cisors of the lower jaw approaches slightly to a trian- 

 gular figure. These teeth, as well as the molars, 

 continue to grow at the base as they are worn down 

 by attrition at the opposite extremity. The molars, 

 like the incisors, are deeply implanted, and hollow 

 at the base ; the foremost on either side of each jaw 

 are separated by a narrow space, (especially those 

 of the upper jaw,) but the series diverge posteriorly. 

 These teeth, when removed from the socket, are found 

 to be considerably curved, so as to form a segment of 

 a circle ; * those of the upper jaw have their convex 

 side placed inwards, and those of the lower jaw are 

 reversed in position : each of the true molars is longer 

 than broad, and nearly divided into two parts by a 



* A molar tooth before me, from the lower jaw of an adult 

 Wombat, forms one-third of a circle of an inch and a half in 

 diameter. 



