502 MONOGRAPHS OF NORTH AMERICAN RODENTIA. 



prominent lobe, bounding the notch posteriorly; and in Iron) of the notch 

 there is also a little prominence, just behind the termination of the margin 



of the ear. The flattened portions of the auricle arc sparsely pilous inside 

 and out, and a tuft of lengthened hairs springs from the front border of 

 the ear. 



The attenuated and elongated muzzle is densely pilous, excepting a 

 small T-shaped nasal pad, divided by a median depression. The upper lip, 

 in particular, is thickly covered with stiffish, flaring hairs, completely con- 

 cealing any median cleft, which may exist, and forming a heavy fringe which 

 droops over and almost hides the incisors; there is an antrorse tuft of bristly 

 hairs on the chin. The openings of the cheek-pouches seem to have no 

 peculiar character, being much as in other species of the genus ; the cavity 

 admits the first joint of one's little finger. The whiskers are very numerous 

 and fine ; the shorter colorless ones seem like mere lengthening of the hairs of 

 the muzzle; others, stiffer and colored, reach rather beyond the head. 

 There are also some long special bristles over the eye, and others between 

 the eye and ear 



The palm proper, and under surfaces of the digits, are perfectly naked, 

 though a considerable fringe of hairs falls down from the wrist. There is a 

 large and conspicuous smooth tubercle on the outer side, at the base of the 

 fifth digit ; two others, one on each side, at the wrist, and others at the bases 

 of the intermediate digits; the disposition of these smaller ones is not very 

 evident in the dried specimens. The thumb is rudimentary, a mere stump, 

 bearing a flattened obtuse nail; the other digits are armed with ordinary 

 compressed, acute, and moderately curved claws ; the 3d is longest ; then 

 come 4th, 2d, and 5th in succession. Of the hind foot, the sole is perfectly 

 naked for its whole length along a median strip, narrowed by encroachment 

 on either side of a fringe of hairs. On the outer side, about half-way from 

 heel to base of digits, is a small tubercle ; there is another near the base of 

 the 1st digit, and a much larger one near the base of the 5th digit, with others 

 still at the bases of the intermediate digits ; but their precise disposition, and 

 the character of the naked sole, cannot be made out perfectly. The first digit 

 is very small, with a smooth bulbous end and short blunt claw ; the other 

 claws are of a more ordinary character, but relatively shorter, blunter, less 

 compressed, and less curved than those of the hand: they are excavated 

 underneath. 



