188 PHILOSOPHY OF ZOOLOGY. 



The animals of this tribe will probably be held in higiier 

 estimation at a future period than they are at present. 

 The seal yields a considerable quantity of oil, the skin is 

 valuable, and the carcase can be converted into manure, 

 or adipocire. The last species might even be used as an 

 article of food, if modern fastidiousness did not prevent 

 the imitation of ancient manners. The seal, which is 

 thus so useful, is easily tamed, and herds of them might 

 be kept in a partially domesticated state, on many parts 

 of the coast, with evident advantage. The otter, too, 

 is easily tamed, and, in a domesticated state, might be 

 found useful in catching fish. We pursue the beasts of 

 the field with dogs, and the birds of the air with hawks, 

 nor would the watery element protect tlie fishes from the 

 chase, were the otter enlisted into our service. 



h. Destitute of tusks. 



GLIRES. 



The animals of this tribe, in the absence of tusks, are 

 ill fitted for tearing their food to pieces. The incisors, 

 usually reduced to two in each jaw, have their edges sharp, 

 placed so as to act against each other, and qualified to nip 

 off small portions of the substances against which they are 

 directed. Their jaws, too, are feeble, and they accomplish 

 their object by efforts, which are frequently repeated. 

 The hind-legs are the longest and strongest, in nearly all 

 the species, reducing their progressive motion to a series 

 of leaps, rather than steps. The clavicles are seldom fully 

 developed. The modifications in this respect, which they 

 exhibit, are employed by Cuvier, in the primary distribu- 

 tion of the genera, although they exhibit no definite line of 

 distinction. 



The intestines are long, and, in many species, there is a 

 very large coccum. The brain presents fewer convolu- 



