► 



iTACEOPODID^. 205 



Subfamily Potoroin-e. 



The first upper incisor is narrow, curved, and much longer than 

 either of the two following teeth (fig. 35) ; an upper canine is 

 present : the fourth premolar is secant and much elongated, with a 

 nearly straight or slightly concave cutting-edge, usually with the 

 vertical grooves and ridges very distinct, and that of the upper jaw 

 without any inner basal ridge : the true molars are quadri-tuber- 

 cular, the fourth being always smaller than the third. 



Genus -ffiPYPRYMNUS, Garrod \ 



The ridges on the foarth premolar are few in number and nearly 

 vertical : the auditory bulla is not inflated ; and there are no palatal 



vacuities. The entepicondylar foramen of the humerus is fi-equentlv 

 absent in both the recent and fossil races of the one species. 



3[fpi)pii)muu5' ruffsccng (Gray-). 



Svn. Bettoyigia rufescens. Gray '. 

 r Betioiigia cuneata, Owen^. 



The fossil mandible figured under the name of B. cuneata appa- 

 rently agrees precisely with the following specimens. 

 Hah. Xew South Wales, 



43618-27. Several imperfect specimens of the cranium and mandible ; 

 from the caves of the ^Velliugton VaUey, Xew South Wales. 

 Several of these and the following specimens belong to 

 immature individuals, and show the fourth premolar in its 

 alveolus. 

 PrestVittd by the Trustees of the Australian Museuiii, 1S70. 



43868-70. Xumerous fi-agments of the maxilla, imperfect mandibular 

 rami, and detached teeth ; from the same locality. 



Same history. 



32316. The anterior portion of the right ramus of the mandible of 

 an immature individual, showing the incisor, pI^Ts, mm. 4, 

 m. 1, m. 2, and pn). 4 in alveola : from the same locality. 



Same histori/. 



* Proc. Zool. Soe. 1875. p. r>9. 



^ Charlesworth's Mag. Nat. Hist. vol. i. p. o8i {l837).—Eettoiiffia. 

 ^ Loc. cit. 



* • Extinct Mammals of Australia,' p. 107, pi. v. fig. 15 (1877). 



