SCIURID^E— SPERMOPHILUS EMPETRA. 



845 



society is generally observed sitting erect on the summit of the hillock, whilst 

 the others are feeding in the neighborhood. Upon the approach of danger, 

 he gives the alarm, and they instantly betake themselves to their holes, remain- 

 ing chattering, however, at the entrances until the advance of the enemy 

 obliges them to retire to the bottom."* It extends southward in the interior 

 at least to Fort Yukon. Mr. B. R. Ross, in notes sent with specimens 

 (labelled "Arctomys kennicottii'') to the Smithsonian Institution, says it is 

 "numerous in the Barren Grounds, as well as along the Arctic Coast, and by 

 no means scarce along the Anderson and Lockhart Rivers ; also numerous 

 below Good Hope, on the Mackenzie; they burrow in considerable numbers, 

 one always acting as sentinel while the others feed and otherwise disport 

 themselves". Most of the specimens in the collection are from the vicinity 

 of Forts Anderson and Yukon. It also extends considerably to the south- 

 westward along the Yukon River ; and Dr. Richardson also gives it as rang- 

 ing on the Pacific coast from British Columbia (formerly New Caledonia) to 

 the Icy Cape.f It also occurs on the Asiatic side of Behring's Strait, and 

 also, according to authors, in Kamtschatka. To the southwestward it passes 

 into the smaller, darker, and longer-tailed var. erythroglutceus, which extends 

 southward to the forty-ninth parallel. 



Table XCI. — Measurements of six skulls of Spermophilus empetha var. empetra. 



* Fauna Boreali-Amerieana, vol. i, p. 158, 1829. 

 t Zo61. Beechey's Voy. Mam. p. 7, 1839. 



