152 CLASS MAMMALIA. 



are bifurcated, and the point of which terminates in the 

 furrow of the lip ; the mouth is not deeply cut ; the incisors, 

 two in number in each jaw, are very apparent, long, narrow,, 

 and trenchant at the extremity, as in all true Rodentia, and 

 the upper ones have no longitudinal furrow in their anterior 

 face. 



M. de Blainville could not observe the number and form 

 of the molar teeth, but he assured himself of the absence of 

 the canines. 



The body of this Gerboa is very large, especially in the 

 posteriors. The belly has neither lateral folds nor pouch, 

 like the Didelphes. The fore-paws, very short, are provided 

 with four distinct toes, armed with crooked nails, and no 

 vestige of thumb is apparent. 



The hinder paws, on the contrary, are considerably de- 

 veloped ; the thighs exceedingly strong and muscular ; the 

 leg extremely long, as is also the metatarsus, which rests 

 altogether on the ground in a state of repose. The toes are 

 three in number, of which the middle is the longest, and 

 is terminated by a very strong claw. The external one is 

 much less thick, and the internal is the smallest. It is 

 easy to satisfy one's self by the touch, that there is but one 

 metatarsian bone for these three toes. In the individual 

 observed by M. de Blainville, the tail was evidently muti- 

 lated ; there remained about two inches of it. 



The fur is extremely soft, thick, and well furnished with 

 hair, altogether analogous to that of the Rabbits. The ge- 

 neral colour is pretty nearly that of the Surmulot, or rather 

 a brown, a little more fawn-coloured above the long hairs, 

 being black at the extremity ; underneath it is entirely 

 white. A large black spot crosses the eye, and extends 

 across the forehead to the other. The end of the muzzle, 

 or rather the extremity of the nose, is of the same colour ; 

 the mustachios are extremely long, very black, and formed 

 of shining hairs, and on each side of the head are two other 



