THEORY OP THE EARTH. " 



lem of its own, all the parts of which mutually cor- 

 respond, and concur to produce a certain definite 

 purpose, by reciprocal reaction, or by combining 

 towards the same end. Hence none of these se- 

 parate parts can change their forms without a 

 corresponding change on the other parts of the 

 same animal, and consequently each of these parts, 

 taken separately, indicates all the other parts to 

 which it has belonged. Thus, as I have elsewhere 

 shown, if the viscera of an animal are so organ- 

 ized as only to be fitted for the digestion of recent 

 flesh, it is also requisite that the jaws should be so 

 constructed as to fit them for devouring prey; the 

 claws must be constructed for seizing and tearing 

 it to pieces ; the teeth for cutting and dividing its 

 flesh ; the entire system of the limbs, or organs of 

 motion, for pursuing and overtaking it; and the 

 organs of sense, for discovering it at a distance. 

 Nature also must have endowed the brain of the 

 animal with instincts sufficient for concealing itself, 

 and for laying plans to catch its necessary victims. 



Such are the universal conditions that are in- 

 dispensable in the structure of carnivorous ani- 

 mals; and every individual of that description 

 must necessarily possess them combined together, 

 as the species could not otherwise subsist. Under 

 this general rule, however, there are several par- 

 ticular modifications, depending upon the size, 

 the manners, and the haunts of the prey for which 

 each species of carnivorous animal is destined or 





