274 ORIOINAL AETI0LE8. 



No. of Species. 



22. Ursus maritimus (Linn.). Polai' Bear. Nait'-suck of the 



Eastern Eskijiios. Common along tlie Arctic coasts. 



II. — OeDER KODENTLi. 



Family Sciuridce. 



(Sciurinse.) 



Grenus Sciurus. 



23. Sciurus hudsonius \\ (Pallas). Cliickaree. Throughout to 



within the Arctic circle. 



Genus Pteromys. 



24. Fteromys alpinus (Eichs.). Eocky Moimtains Plying Squirrel. 



Pound on the mountain ranges of the Liard Eiver : rather 

 rare. 



Genus Tamias. 



25. Tamias quadrivittatus || (Eichs.). Missouri Striped Squirrel. 



Prom lat. 33° 30' to 67° North : very abundant on the 

 Liard Eiver. 



Genus Arctomys. 



26. Arctomys monax || (Gnielin). Ground Hog. South Carolina 



to 62° North : rare. 



27. Arctomys pruinosus (Gmelin). North to Arctic circle: abun- 



dant on the mountain ranges. 

 28 Arctomys Kennieottii (Eoss). This I consider to be a new 

 species ; but I may be wTong. It is of small size, and 

 inhabits the Northernmost ranges of the Eocky Mountains. 



(Castorin89.) 



Genus Castor. 



29. Castor canadensis |1 (Kuhl). Beaver. Isa, of the Chipewyan 



Indians. Throughout North. America to within the Arctic 

 circle : very abimdant. 



Family Muridce. 



(MurinsD.) 

 Genus Jaculus. 



30. Jaculus hudsonius \\ (Wagler). Jumping Mouse. Pennsyl- 



vania to Youcon Eiver. Common at Portage-la-loclie : 

 rare, in McKeuzie's Eiver. 



Gen VIS Hesperomys. 

 81. Hesperomys myoides \\ (Gapper). Hamster Mouse. New 

 York to Arctic Sea. Very abundant, east of the Eocky 

 Mountains : not found westward, on the Youcon Eiver. 

 This species is very annopng in dwellings, as it carries off 

 quantities of sugar, rice, &c., in its cheek-pouches, to store 

 for its winter consumption. 



