MUS SETIFER. 
the posterior extremities the three intermediate toes are largest ; they are robust, 
and nearly of equal length ; the outer and inner toes are smaller ; the latter is consi- 
derably removed from the others, and admits a more lateral motion. Underneath, 
the feet are naked, and provided with prominent tubercles. 
The body is posteriorly lengthened towards the uropygium or vent, affording 
thus a conical base to the root of the tail. This organ is nearly cylindrical, and 
very gradually attenuated to an obtuse point : it is covered with numerous delicate 
membranaceous rings ; the disposition of these is regular in the highest degree ; they 
are made up of oblong scales, placed in close contact, so as to exhibit the appearance 
of rings with crenulated margins, in which the separate squamae are not perceptible. 
The tail is more naked than that of the Mus decumanus ; a few short delicate hairs 
arise, in very small tufts of two or three, from the scales composing the rings. 
The colour of our animal is dark brown above, and grayish underneath. The 
tint is more uniform than in the common Brown Rat. The separate hairs are gray, 
or tawny, at the base, and dark at the extremity, by which a slight variegation is 
produced on the surface. The covering is throughout rough and bristly ; the hairs 
are short on the head and on the under parts generally, and they are here supplied 
with a little down at the base; among these, the rigid hairs or bristles, which give a 
character to our animal, are copiously scattered ; they have an oblique direction 
on the back and the adjoining portions of the sides ; they are here nearly an inch 
long ; but on the rump they increase in length and in substance ; their direction is 
more regular, and they constitute a lax covering about the posterior parts, which 
projects considerably beyond the body, and terminates in an abrupt manner. 
Several points of agreement between the Mus setifer and the Mus decumanus, 
or Brown Rat, have already been enumerated: in my comparisons with other 
species of this genus, I have had the assistance only of figures and descriptions. 
Besides the peculiar rough and bristly character of its hair, our animal differs from 
the Brown Rat in the extraordinary size of its ears, in the strength of its front 
teeth, in the comparative nakedness of the tail, and in several minuter particulars 
in its form and proportions, which, although not easily expressed by words, become 
obvious by comparison. Among other Indian Rats the Mus giganteus and the 
Mus perchal have some affinity to it. The former is carefully described by General 
Hardwicke, in the Vllth Volume of the Linnean Transactions ; and detailed draw- 
ings, accompanied with notices as to its size, have been received at the Honourable 
