. PLAGIAULACID^. 195 



M. 1525. Cast of the right radius. The original, of which the 

 history is the same as that of No. M. 1526, is figured by 

 Owen, op. cit. pi. xl. figs. 1-3. 

 Presented by the Trustees of the Australian Museum, 1883. 



M. 1523. Cast of the left innominate. The original, of which the 

 history is the same as the last, is figured by Owen, op. cit. 

 pi. xlvi. fig. 1 ; it closely resembles the corresponding 

 bone of Phalangista. 

 Presented by the Trustees of the Australian Museum, 1883. 



M. 1526. Cast of an ungual phalangeal. The history of the original 

 is the same as that of the last. The bone was evidently 

 covered by a horny claw, like that of Plialanyista. 

 Presented by the Trustees of the Australian Museum, 1883. 



M. 3666. A right calcaneum, perhaps belonging to a young indi- 

 vidual of this species ; from a cave in the Wellington 

 Valley. 



Presented by the Trustees of the Australian Museum. 



Family PLAGIAULACID^. 



This and the three following families, forming the suborder Multi- 

 tuberculata of Cope \ are regarded as primitive Diprotodonts, pre- 

 senting, however, some very specialized characters, and are pro- 

 visionally placed here. They are characterized by the true molars 

 carrying longitudinal rows of tubercles, separated by one or more 

 grooves ; there being either two or three such rows in the upper 

 molars of those forms in which these teeth are known, while there 

 Pig. 29. 



^^w fwMftr ^^^ 



Neoplagiaulax eoccenus, Lemoine. Oral and lateral views of an upper true 

 molar ; from the Lower Eocene of JJheims. a. Nat. size. (From the 

 ' Quart. Journ. Geol. Soc.') 



are, at least usually, only two in those of the lower jaw. The 

 external surface of the masseteric fossa of the mandible has neither 

 pit nor perforation, as in the Phalanyistidce. In the present family, 

 the number of upper incisors was probably two or three 2 ; the lower 

 prcmolars have a highly convex cutting-edge, and are always large, 

 compressed, and usually either serrated, or obliquely grooved and 



1 Ainer. Nat. vol. xviii. p. 687 (1884). 



2 Lemoine describes two incisors and a canine in Xeoplagiaulax, 



o2 



