30(J ADDENDA. 



These mounds, sometimes about two feet in heighty 

 and four in diameter, are occupied as watch towers 

 by the inhabitants of these little communities. 

 The Squirrels, one or more, are irregularly dis- 

 tributed on the tract they thus occupy, at the dis- 

 tance of ten, twenty, or sometimes from thirty to 

 forty yards. When any one approaches, they 

 make a shrill whistling sound, somewhat resem- 

 bling tweet, tiveet, tweet, the signal for their party 

 to take the alarm, and to retire into their intrench- 

 ments. They feed on the roots of grass, &c. 



Inhabit the plains of Columbia. (Lewis and 

 Clark.) 



Species. 



2. Arctomys latrans, (nob.) 

 Barking Squirrel, Lewis and Clark's Exped. 

 up the Missouri, vol. ii. p. 175. 



Char. Essent. Colour a uniform brick-red, 

 lighter beneath ; cheeks furnished with pouches ; 

 a few long hairs are inserted on each jaw, and 

 directly over the eyes. 



Dimensions. From the extremity of the nose to 

 the end of the tail, one foot five inches ; tail, four 

 inches ; weighing about three pounds. 



Description. Colour of a uniform brick-red, the 

 former predominating ; the under side of the neck 

 and belly are lighter than the other parts of the 

 body ; the legs are short, and the breast and 

 shoulders wide ; the head is stout and muscular, 



