80 MAMMALIA. 



parts of it exceed those of the front; so that they rather leap than walk. In 

 some of them this disproportion is even as excessive as it is in the kan- 

 guroos. 



In the whole of this class, the brain is almost smooth and without furrows ; 

 the orbits are not separated from the temporal fossae, which have but little 

 depth, and the eyes are altogether lateral. The trigomatic arches, which are 

 thin and curved below, announce the weakness of the claws ; the fore arms 

 have nearly lost the power of rotation, and their two bones are often united. 



The inferiority of these animals is visible in most of the details of their 

 organisation. Those genera, however, which possess stronger clavicles, 

 have a certain degree of dexterity, and use their fore feet to convey their food 

 to the mouth. 



Some of them even climb with facility. The 



SCIURUS, Linnaeus. 



Squirrels are distinguished by their strongly com- 

 pressed inferior incisors, and by their long tail fur- 

 nished with hairs. They have four toes before, and 

 five behind. The thumb of the fore foot is some- 

 times marked by a tubercle. They have in all four 

 grinders, variously tuberculated, and a very small additional one above in 

 front, that very soon falls. The head is large, and the eyes projecting and 

 lively. They are light and active animals, living on trees, and feeding on 

 fruits. 



SCIURCS, Cuvier. 



In the Squirrel, properly so called, the hairs of the tail are arranged on 

 the sides, so as to resemble a feather. There are a great many species in the 

 two continents. 



Sc. vulguris, Buff. (The Common Squirrel.) The back of a lively red ; 

 belly white ; ears terminated by a tuft of hair. Those of the north, in winter, 

 become of a beautiful blueish ash colour, producing the fur called minever 

 when taken only from the back, and vair (by the French) when it consists of 

 the whole skin. 



The American species have no pencils to their ears. 



The CAT SQUIRREL (Sc, cinereus, Lin.) of America is cinereous at>ove, white 

 beneath; tail less distichous than that of the other species with which it has 

 been confounded; there are but four teeth in the upper jaw on each side. The 

 GREY SQUIRREL, (Sc. Carolinensis, Lin.) Above mixed white, blackish, and 

 rusty ; beneath, white ; cheeks rusty ; tail as long as t'ie body, edged with 

 white; upper jaw five teeth on each side; this was described in the French 

 edition as the S. cinereus. 



It is probable that we shall have to separate from the Squirrels certain 

 species which have cheek pouches like the Hamsters, and pass their lives in 

 subterraneous holes ; the Tamia of Illiger. For instance, the 



Sc. striatwt, Lin. (The Ground Squirrel.) Which is found throughout all 

 the north of Asia and America, particularly in the pine forests. The tail is 



