280 Zoological Society. 



The Hudson's Bay Squirrel, a well-known species, is a third 

 smaller than the Northern Gray Squirrel ; tail shorter than the 

 body ; eara slightly tufted. Colour, reddish above, white heneath. 

 Dental formula : incis. -, can. J^, mol. |^|,^20. 



Sciurus Richard8oni, Cohnnbia Pine Squirrel. 



Small Brown Squirrel. Lewis and Clarke, vol. iii. p. 37. 



Sciurus Hudsonius, var. (i. Columbia Pine Squirrel. Richardson, 

 Fauna Boreali- Americana, p. 190. 



Smaller than Sc. Hudsonius', tail shorter than the body ; rusty 

 gray above, whitish beneath; extremity of the tail black. 



This small species was first noticed by Lewis and Clarke, who 

 deposited a specimen in the Philadelphia Museum, where it still 

 exists. I have compared it with the specimen brought by Dr. 

 Townsend, and find them identical. Dr. Richardson, who appears 

 not to have seen it, supposes it to be a mere variety of the Sciwus 

 Hudsonius. 



Dental formula : incis. |, can. Q ^, mol. ^-*, = 20. 



" The body of this most diminutive of all the known species of 

 genuine squirrel in North America, is short, and does not present 

 that appearance of lightness and agility which distinguishes the 

 Sciurus Hudsonius. Head large, less elongated, forehead more 

 arched, and nose a little blunter than Sc. Hudsonius ; ears short ; 

 feet of moderate size. The third toe on the fore-feet but slightly 

 longer than the second ; the claws are compressed, hooked and 

 acute ; tail shorter than the body ; the thumb-nail is broad, flat and 

 blunt. 



" The fur on the back is dark plumbeous from the roots, tipped 

 w T ith rusty brown and black, giving it a rusty gray appearance. 

 It is less rufous than the Sc. Hudsonius, and lighter coloured 

 than the Sc. Douglasii. The feet on their upper surface are 

 rufous : on the shoulders, forehead, ears, and along the thighs, 

 there is a slight tinge of the same colour. The whiskers, which are 

 a little longer than the head, are black. The whole of the under 

 surface, as well as a line around the eyes, and a small patch above 

 the nostrils, smoke-gray. The tail for about one half its length 

 presents on the upper surface a dark rufous appearance, many of the 

 hairs being nearly black, pointed with light rufous : at the extremity 

 of the tail, for about an inch and three-fourths in length, the hairs 

 are black, a few of them slightly tipped with rufous. The hind-feet, 

 from the heel to the palms, are thickly clothed with short adpressed 

 light- coloured hairs ; the palms are naked, The sides of the body 

 are marked by a line of black commencing at the shoulder and ter- 



