26 ORDERS OF 



the hard shells that contain them. A few of the species 

 may be considered as omnivorous, since they will devour, 

 with avidity, almost all kinds of substances, both animal 

 and vegetable. Their front-teeth grow again as fast as 

 they are worn down by gnawing. Those of the animals 

 which subsist entirely on vegetables, have their grinders 

 flat on the crown ; but such as feed on mixed animal and 

 vegetable substances, have the crowns of the grinders ele- 

 vated into blunt tubercles, or sharp points, according to 

 the general nature of their food. 



Most of the Glires have a perfect thumb on each of 

 their feet; but in the Hares this is very short, and in 

 the Rats and Squirrels it is so diminished, as to have 

 only two phalanges or joints. The toes of Rats, Squir- 

 rels, and Hares, have only the two last joints separate. 



In the form of their bodies the Glires have this pecu- 

 liarity, that their hinder parts are generally more elevated 

 than the shoulders, from their posterior legs being longer 

 than the anterior ones. It is in consequence of this dis- 

 proportion of the limbs that the animals do not, in fact, 

 either walk or run, but perform their motions by a suc- 

 cession of leaps. 



All the British species have their bodies covered with 

 hair. 



The intestines of the Glires are generally very long. 

 Their stomach also is long and simple; and the ccecum 

 extremely voluminous, sometimes even larger than the 

 stomach. Squirrels and Rats have their clavicles, or 

 collar-bones, perfect: Hares have these suspended in the 

 flesh. 



PECORA. 



