99 



along the Mississippi, and is said to be abundant in its favourite lo- 

 calities. 



" As yet I am unacquainted with any species of Squirrel fully 

 agreeing with Sc. ruf venter." 



Sciurus Donglasii, Gray. Oppoce-poce, Indian name. 

 A species about one-fourth larger than the Hudson's Bay Squirrel ; 

 tail shorter than the body. Colour : dark brown above, and bright 



buiF beneath. Dental formula ; incis. g, can.~-Q, mol. |5^,=20. 



The incisors are a little smaller than those of Sc. Hudsonius. In 

 the upper jaw, the anterior molar, which is the smallest, has a single 

 rounded eminence on the inner side ; on the outer edge of the 

 tooth there are two acute points, and one in front ; the next two 

 grinders, which are of equal size, have each a similar eminence on 

 the inner side, with a pair of points externally; the posterior 

 grinder, although larger, is not unlike the anterior one. In the 

 lower jaw the bounding ridge of enamel in each tooth forms an an- 

 terior and posterior pair of points. The molars increase gradually 

 in size, from the first, which is the smallest, to the posterior one, 

 which is the largest. 



This species in the form of its body is not very unlike the Sc. Hud- 

 sonius ; its ears and tail, however, are much shorter in proportion. 

 In other respects also, as well as in .size, it differs widely. 



Head considerably broader than that of Sc. Hudsonius ; nose less 

 elongated and blunter ; body long and slender ; ears rather small, 

 nearly rounded, slightly tufted posteriorly ; as usual in this genus, 

 the third inner toe is the longest, and not the second, as in the 

 Spermophiles. The whiskers, which are longer than the head, are 

 black. The fur, which is soft and lustrous, is on the back, from 

 the roots to near the points, plumbeous, and at the tip brownish 

 gray ; a few lighter coloured hairs interspersed, gives it a dark 

 brown tint : when closely examined it has the appearance of being 

 thickly sprinkled with minute points of rust colour on a black ground. 

 The tail, which is distichous but not broad, is for three-fourths of its 

 length of the colour of the back ; in the middle the hairs are plum- 

 beous at the roots, then irregular markings of brown and black, 

 and tipped with soiled white, giving it a hoary appearance ; on the 

 extremity of the tail the hairs are black from the roots, tipped with 

 light brown. The inner sides of the extremities and the outer sur- 

 faces of the feet, together with the throat and mouth, and a line 

 above and under the eye, are bright buiF. 



The colours on the upper and under parts are separated by a line 

 of black, commencing at the shoulders and running along the flanks 

 to the thighs. It is widest in the middle, where it is about three 

 lines in width, and the hairs, which project beyond the outer 

 margins of the ears, and form a slight tuft, are dark brown, and in 

 some specimens black. 



Dimensions. in. lines. 



Length from point of nose to the insertion of the tail 8 4 



Tail (vertebrae) 4 6 



Tail including fur 6 4 



