132 



SCIURUS. 



The Chickarees, or Red Squirrels, comprising the last sub-genus 

 of Sciurus, are boreal in their range and are found as far north as 

 the limit of trees. So far as known, only one subspecies penetrates 

 into Mexico, and this is confined to the San Pedro Martir Mountain 

 range of Lower California, where probably by a lofty altitude it 

 counteracts the effects of a more southern latitude. The tail of the 

 Red Squirrel is smaller than that of the gray squirrel group and its 

 allies, and the ears are often tufted or penciled in winter, and the 

 species represent in America the common squirrel of Europe. Like 

 many species of Tamias, at certain seasons the Chickarees have a 

 black line along the side dividing the color of the upper and under 

 parts. 



I. Tamiasciuras, Chickarees. 



Premolars, { 7 or ^. Skull short, broad, depressed between 

 orbits; superior outline greatly curved, highest point between post- 

 orbital process of the frontal; rostrum short, broad; nasals broad, not 



FIG. 21. SCIURUS <TAMIASCIURUS^ D. MEARNSI. 

 No. 25170 U. S. Nat. Mus. Coll. Nat. size. 



