OF DIPUS, OR JERBOA. 115 



fentations of thefe animals. The drawing which accom- 

 panies this paper has been made with great care, all the 

 proportions being preferved with the moft fcrupulous 

 nicety. My defcription, therefore, fhall not be long. 



In its general habit, or appearance, the animal of 

 which i am fpeaking is nearly allied to the murine, or 

 mice, tribe. But it differs from the true mice fo elfen- 

 tially, in feveral particulars, that I have no hefitation in 

 feparating it from them, and in arranging it with the 

 genus DiPUS of Schreber, Gmelin, and fome other fyf- 

 tematic writers on natural hiftory. Of this genus I be- 

 lieve it to be a new fpecies, which I have taken the 

 liberty to call Dipiis Americanus. 



This animal is about the fize of the common houfe- 

 moufe. I weighed two of them. The difference in 

 their weight was very fmall. That of which I have 

 given a figiu-e, and from which the following defcription 

 is principally taken, weighed nine penny-weight, and 

 twenty-tVi^o grains, foon after the death of the animal, 

 and before the bowels were taken out. Like all the other 

 fpecies of Dipus, this is furnifhed with two doites pri- 

 7uores, or cutting teeth, in each jaw. Thefe teeth are 

 iharp at the pointvS, and of a chefnut-brown colour. The 

 upper-jaw projetls coniiderably beyond the lower. The 

 noftnls are open. The whiflcers are long. The cars 

 :ire fmall, fomcuhat oval, and covered. The fore-feet, 

 or rather arms, are fliort, and are furnifheJ with four 

 toes or fingers, the nails of which are long, and very 

 lliarp. Belides thefe fingers, there is a. kind of minute 

 tal'-erculum, in place of a thumb. 'I his tiiberculum is 

 entirely deflitute of a nail. The hind legs are very long, 

 and arc furnilhed with five toes, the three middle ones 

 being long, 'lender, and nearly of an equal length. The 

 two iide-toes are much Ihortcr. The inner tee is the 

 iLorteft of the five. 



The 



