464 SQUIRRELS AND GROUND SQUIRRELS . CHAP. 



postorbital processes. The infra-orbital foramen is, as a rule, not 

 large, but is increased in size in a few forms. The number of 

 separate pieces of bone in the sternum is five. The molars of the 

 upper jaw are five, but the first is very small and soon drops out. 



The Squirrels are often rather brilliantly coloured. The 

 Chinese Sc. castaneiventris has grey fur with a rich chestnut- 

 coloured under surface. The Malabar Squirrel, Sc. maximus, as 

 its name implies, a large animal, has a deep reddish or chestnut- 

 coloured fur above, which becomes yellow below. The " Common 

 Squirrel," " the lytill squerell full of besynesse," which is the 

 Squirrel of this country, is brownish red on the upper parts and 

 white below. It ranges from this country as far east as Japan. 

 Like many other Eodents the Squirrel likes animal food and will 

 eat both eggs and young birds. " Camel's hair " brushes are 

 made from this animal. The genus Tamias, almost exclusively 

 North American in range, is included by Dr. Forsyth Major l 

 in this genus, which then consists of considerably over one 

 hundred species. 



The Ethiopian Ground Squirrels, genus Xerus, have a more 

 elongated skull than Sciurus, and the postorbital processes are 

 shorter. The feet are not hairy. 



Nannosciurus forms a perfectly distinct genus of Squirrels. 

 These " Pygmy Squirrels " differ in possessing a very elongated 

 " face " and in the very broad frontal region. The teeth are 

 unlike those of Sciurus in certain features, and have been 

 especially compared by Forsyth Major to those of the Dormice. 

 Four species of this genus are Malayan ; one is West African. 



The Bornean Rheithrosciurus macro tis is the only species of 

 its genus. The genus may be distinguished by the exceedingly 

 brachyodont molars, this feature being more marked in this genus 

 than in all other Squirrels. It is called the " Groove-toothed 

 Squirrel," from the " seven to ten minute parallel vertical grooves 

 running down the front face of its incisors." 2 



The genus Spermophilus includes a large number (forty or so) 

 of Palaearctic and Nearctic animals known as Sousliks. The ears 

 are small ; there are cheek pouches as in Tamias. The general 

 aspect of the animal is like that of a Marmot, and they bridge over 

 the exceedingly narrow gap which separates the Marmots from 

 the true Squirrels. Anatomically the skull is like that of 



1 Proc. Zool. Soc. 1893, p. 179. 2 Flower and Lydekker. 



