62 



MAOKOPODID^. 



Type in the Paris Museum. 



Although the cranial and dental characters of M. hraehyurus 

 show no approximation to those of Potorous, yet externally it so 

 strikingly resembles the members of that genus found in the same 

 region that its confusion with one of them would be by no means 

 improbable. It may, however, always be distinguished either from 

 P. gilberti or P. platyops by its longer feet, larger and propor- 

 tionally shorter and thicker head, hairier ears, and grey instead of 

 rufous-tipped underfur. 



„ I Ad. sk. I J, King George's Sound, W. A. John Gilbert, Esq. 

 "• \ Skull, f "^^ [0.]. - 



b. Imm. St., $ . King George's Sound, W. A. Gould Coll. 



{J. Gilbert). 



^ I Imm. St. I p Perth, W. A.. {J. Gilbert). Gould Coll. 



I Skull. ( + ■ (b Sc c. Co-types of H. brevicaudatus, Gray.) 



d. Imm. ak., § . Augusta, W. A. {J. Gilbert). Gould Coll. 



2. PETROGALE. 



Type. 

 Heteropus, Jourd. C. R. v. p. 522, Oct. 1837; Ann. Sci. 



Nat. (2) viii. p. 368 (1837). {Nee Pal. de Beam. 



1805, Orthoptera; nee Fitzinger, 1826, Reptilia.) P. penicillata. 



Petrogale, Gray, Charlesw. Mag. N. H.i. p. 583, Nov. 



1837 P. penicillata. 



Ehinarium naked. Fur on back of neck directed downwards. 

 Central hind claws very short, only exceeding the toe-pads by two 

 or three millimetres. Tail long, cylindrical, not so thick as in 

 Macropus, thickly haired and pencilled at its extremity. 



Skull as in the smaller members of the genus Macropus. Supra- 

 orbital edges well developed, more or less overhanging. Palatal 

 foramina short. Bony palate with large vacuities. BuUse sometimes 

 more or less inflated. 



' dentition :-I. ^, C. ?, P. :4^, M. J-^l^^ x 2=32. 



Incisors small and light ; i.^ very similar to that of Ma^iropus 

 hraehyurus, viz. small, delicate, with a well-marked notch about its 

 centre, the part behind the notch nearly as long as that in front. 

 P." large and heavy, very similar in all the species, resembling in 

 shape and size that of certain of the smaller Wallabies, such as 

 M. coxeni or wileoxi; a well-marked internal ledge running its 

 whole length, and two or three indistinct vertical ridges on its 

 external side. Molars as in the Wallabies (Macropus, grouns II 

 &III.).^ r > b i- 



Bange. The whole of Australia, but not Tasmania. 



Although very closely allied to the second and third groups of the 

 genus Macropus, the Rock-Wallabies are, on the whole, fairly 

 entitled to generic separation, as they form a natural and easily 

 definable group. Their habits differ considerably from those of the 

 plain-loving Wallabies, as they inhabit rooky regions, climbing 



