328 PEOF. B. coLLETT ON :NrAMMALS [Mar. 16, 



21. Bettongia lesueuri (Quoy & Gaim.), 1824. 



Bettongia lesveitri, Thos. Cat. Mars. Monotr. Brit. Mus. p. 112 

 (1888); Ogilby, Cat. Austral. Mamm. p. 41 (1892). 



If.W. Australia: Eoebuck Bay, Nov.-Dec. 1895 (seven speci- 

 meus, three young ones, one embryo). 



There are in the collection, besides the seven skins, three young 

 ones from the pouch (size of a rat), one embryo (length about 

 26 mm.), and eight extra skulls, all from Eoebuck Bay. 



SJcin. In some specimens the tail shows traces of a low- 

 crest of darker colour towards the tip. Back rather variable in 

 colour, greyish in some, more reddish in others. Tip of tail not 

 white in the seven adult specimens at hand ; but in two young 

 ones (from the pouch, size of a small rat) the tip is white for 5 to 1 

 inch. Arms and legs pale brown, hands darker reddish brown. 



Skull. The largest skull has a length of 71 mm., breadth 45 mm. 

 In some specimens the frontal crests meet posteriorly and form a 

 short and low sagittal crest. 



Teeth. P* has 10 external grooves (in some specimens 9). 



In one specimen the canine has two cusps, very distinct on the 

 left, less on the other side. 



Hah. Very numerous around Eoebuck Bay, burrowing in the 

 sand-hills. 



Native name : Jalva. 



Fam. Phalakgerid^. 



22. Tetchosueus vulpecitla (Kerr), 1792. 



Trichosurus vulpecuh, Thos. Cat. Mars. Monotr. Brit. Mus. 

 p. 187 (1888) ; Ogilby, Cat. Austral. Mamm. p. 78 (1892). 



iV. Australia ; Daly Eiver, July-Aug. 1894 (eleven specimens, 

 three embryos, two young in spirit, one skeleton). Katherine 

 Eiver, July'l3th-14th, 1894 (two specimens). 



Sl-in. These specimens seem to form a distinct race (var. 

 arnhemensis), characterized by their inferior size and the scantily 

 clothed tail. 



Length of head and body (measured from the skin) about 

 360 mm. ; tail 250 mm. 



The exterior two-thirds of the tail is naked below, and on the 

 sides, and the black hairs form a crest along the upperside, but 

 leaving the tip itself almost bare. 



Colour variable, in most specimens (typical) grizzled grey, in 

 others reddish brown, with all transitions between them. Distal 

 part of the tail black ; iu one specimen it has a faint trace of 

 white on the extreme tip. 



Chin blackish, as in the type form ; the reddish-brown longitu- 

 dinal patch on the centre of chest also present in most specimens. 



Sl'ull. Nine skulls, all of which with the teeth fully developed 

 have the following size : — 



Largest specimen : length 80 ; breadtli 48 mm. 



