472 



CARNIVORA. 



greater aberration from the type, in the planti- 

 grade form of the foot, by which the animal is 

 enabled to walk with that solidity and firmness 

 which the less degree of mobility in the rest 

 of the skeleton renders necessary, or to climb 

 trees, or dig the ground, in pursuit of the 



various food from which the different genera of 

 this family derive their nutriment. The small 

 extent of the lumbar portion of the spine com- 

 pared with the dorsal which we find in some 

 of this tribe, is equally characteristic. 



In the Phocidae or Seals, (jig. 191 j, on the 



Fig. 191, 



other hand, the most 

 remarkable deviation 

 from the typical struc- 

 ture is seen in the adaptation of 

 the limbs to the aquatic residence 

 and habits of the animals. The 

 posterior members are extended 

 backwards in a horizontal direc- 

 tion, forming two broad fins, by 

 which they swim with great facility 

 and strength. The anterior feet are 

 similarly constructed, but they serve 

 also in some measure for progres- 

 sion on land, though to a limited 

 extent. The cranium is thin and 

 round, and the teeth, sharp and 

 many-pointed, are formed for seiz- 

 ing, holding, and tearing fish, the activity of 

 whose motions, no less than their scaly surface 

 and even, rounded form, render such a structure 

 absolutely necessary. 



The cranium. The peculiarities by which 

 the cranium of this order is distinguished have 

 reference, not to the form and developement of 

 the brain only, but particularly to the character 

 of the food, and the consequent necessity of 

 peculiar powers of mastication, and of the 

 other acts preparatory to the function of diges- 

 tion. We shall find, therefore, not only that 

 the general form of the skull in the whole of 

 the Carnivora is diffe- 

 rent from those of every 

 other group, but that the 

 families composing it 

 differ in miror points of 

 structure, w:tn the same 

 relation to aliment and 

 habits. The cranium in 

 this order then is cha- 

 racterized, when com- 

 pared with that of most 

 other orders, especially 

 those which feed on 

 grain or other substances 

 requiring long and la- 

 borious trituration, by 

 great shortening of the 



bones of the face. This is particularly con- 

 spicuous in the cats, (fig. 192,) the seals, 



Fig. 192. 



(Jig. 193,) and even the hyenas, but is less 

 Fig. 193. * 



so in the bears (fig. 194) and dogs. 

 Fig. 194. 



The 



