STRUCTURE OF THE MOUTH. 261 



as an essential character of Accentor, because it is 

 manifested by an external conformation, which in- 

 dicates such habits. This instance, out of number- 

 less others, is a convincing proof that not even a 

 difference in the nature of their food will invariably 

 or completely detach insectivorous from granivorous 

 birds. On looking, however, to the great divisions 

 in every class of zoology, we see that no characters 

 can be more natural than such as separate destroy- 

 ing from harmless animals among quadrupeds. The 

 most ferocious genera are brought together in 

 the order Ferce, composed entirely of the beasts of 

 prey : here we have the lion, the tiger, and all the 

 races of leopards, panthers, and cats ; together with 

 the w r easels, polecats, and those minor blood-sucking 

 quadrupeds, as destructive and sanguinary towards 

 the smaller animals, as the former are to the larger. 

 These find their representatives in the rapacious 

 order of birds ; and in both, the nature of their food 

 is at once explained by the construction of their 

 mouth : the teeth of one, and the notched bill of the 

 other, being especially adapted for tearing flesh. 

 Extending this analogy to the insect world (which, 

 by the way, has never yet been done correctly), we 

 find the great majority of Aptera, or the wingless 

 orders, — as the spiders, scorpions, crabs, &c. — 

 feeding in like manner upon other insects, and living 

 only upon the blood and flesh of their victims. So 

 strongly, indeed, has nature preserved this distinction 

 between her types of evil and of good, or, to drop 

 metaphor, between noxious and innoxious animals, 

 that not only are these the essential distinctions of 

 her primary groups in every class, but they can be 

 s 3 



