242 



respect a true Mas, and is an inhabitant of the open plains of Dar- 

 ling Downs, New South Wales ; its incisor teeth, when compared 

 with those of M. assimilis, are broad and less elongated ; its hair 

 also is coarser, and more wiry. Its colouring is as follows : — 



MUS SORDIDUS. 



Head, all the upper surface, and flanks clothed with a mixture of 

 black and brown, the former hue prevailing along the centre of the 

 back, and both nearly equal in amount on the flanks ; whiskers 

 black ; under surface greyish-buff ; hind feet silvery-grey ; fore feet 

 greyish-brown ; tail thinly clothed with extremely fine black hairs. 



Total length from nose to base of tail. ... 6-| inches. 



of the tail 5 ,, 



of the fore-arm -^ « 



of the hind leg and toes. ... 1-| „ 



Hab. Open plains of Darling Downs. 



Remark. — The name of sordidus has been assigned to this animal 

 from the dark colouring of its upper surface. 



The third species to which Mr. Gould called attention is a remark- 

 able black Eat of nearly the same size as, and of a similarly delicate 

 form to the, Black Rat of Europe (Mus Ratius), but from which it 

 differs in having the tip of the nose, the front part of the lips, a 

 longitudinal stripe on the breast, the hind and fore feet, white. For 

 this he proposed the name of 



MUS MANICATUS. 



Head, ears, and all the upper surface black, gradually passing into 

 the deep grey of the under surface ; nose, fore part of the lips, stripe 

 down the centre of the throat and chest, hind and fore feet, white ; 

 whiskers deep black ; tail denuded of hairs. 



Length from nose to base of tail .... 7 inches. 



of the tail 5 „ 



of the fore-arm 1^ „ 



of tarsi and toes 1-f ,, 



Hab. Port Essington. 



Remark. — This animal was presented to Mr. Gould by J. B. 

 Turner, Esq. 



The fourth is a very diminutive Rat, with coarse hair and a some- 

 what short tail ; it is even smaller in size than the Mus Gouldi and 

 M. gracilicauda, but is more nearly allied to the latter than to any 

 other. Three or four specimens, all of the same size, are contained 

 in the collection at the British Museum, and there are others in the 

 Derby Museum at Liverpool, all of which were collected by Mr. 

 Gilbert on the Victoria Plains, Western Australia. 



MuS NANUS. 



Head, all the upper surface, flanks, outer sides of the limbs, and 



