HYDROMYS FULIGINOSUS, Gould . 
Sooty Beaver-Rat. 
Ngoor-joo, Aborigines of Perth, Western Australia. 
Ngwir-ri-gin, Aborigines of King George’s Sound. 
The specimens of this animal in my collection were procured in the neighbourhood of the lakes near 
Perth and at King George’s Sound in Western Australia, by the late Mr. Gilbert, who in his letter to me on 
the subject expressed his opinion that they were quite different from any other species he had seen ; and 
surely an animal so different from all its congeners in the colouring of the body, in the darker colour of 
the hinder, and the greyish white hue of the fore feet, may with propriety be considered as specifically 
distinct. Independently of these differences, I may mention, that the uniformity of the body tint is all but 
unbroken, the face, the centre of the back, and the basal portion of the tail being simply a trifle darker than 
the rest of the fur. Mr. Gilbert hints that the H. chrysogaster also inhabits Western Australia, but in 
this I believe he was mistaken ; in all probability the South Australian species, to which I have given the 
name of fulwlamtus, is the animal he saw, but failed to procure. 
Fur of the upper surface mingled huffy brown and black, the latter hue predominating and producing a 
deep sooty appearance, especially along the back, whence the specific name ; whiskers and fur of the face 
black ; that of the tail is also black, except the apical inch and a half, which is white ; fur of the under 
surface pale greyish brown ; fur of the outer surface of the limbs dark brown, of the fingers white ; nails 
white. 
The figures are rather less than the size of life. 
