428 HISTORY OF 



Man's head, whether considered externally or in- 

 ternally, is differently formed from that of all 

 other animals, the monkey kind only excepted, 

 in which there is a striking similitude. There 

 are some differences, however, which we shall 

 take notice of in another place. The bodies of 

 all quadruped animals are covered with hair ; but 

 the head of man seems the part most adorned, 

 and that more abundantly than in any other ani- 

 mal. 



There is a very great variety in the teeth of 

 all animals : some have them above and below ; 

 others have them in the under jaw only ; in some 

 they stand separate from each other ; while in 

 some they are continued and united : The pal- 

 ate of some fishes is nothing else but a bony plate 

 studded with points, which perform the offices of 

 teeth. All these substances, in every animal, 

 derive their origin from the nerves ; the sub- 

 stance of the nerves hardens by being exposed to 

 the air ; and the nerves that terminate in the 

 mouth being thus exposed, acquire a bony soli- 

 dity. In this manner, the teeth and nails are 

 formed in man ; and in this manner, also, the 

 beak, the hoofs, the horns, and the talons of 

 other animals, are found to be produced. 



The neck supports the head, and unites it to 

 the body. This part is much more considerable 

 in the generality of quadrupeds, than in man. 

 But fishes, and other animals that want lungs 

 similar to ours, have no neck whatsoever. Birds, 

 in general, have the neck longer than any other 

 kind of animals : those of them which have short 



