82 SPECIAL SENSES. 



set with little stiff points ; sometimes fibrous, and fringed at 

 the edges. In the parrots, it is thick and fleshy ; or it is even 

 harbed at its point, as in the woodpeckers. In some reptiles, 

 the crocodile, for example, the tongue is adherent; mothers, on 

 the contrary, it is capable of extensive motion, and serves as an 

 organ of touch, as in the serpents ; or it may be thrust out to a 

 great length, to take prey, like that of the chameleon, toad, and 

 frog. In fishes it is usually cartilaginous, as in birds, and is 

 generally adherent, and has its surface frequently covered with 

 teeth. 



1/2. It is to be presumed, that in animals which have a 

 cartilaginous tongue, the taste must be very obtuse, especially 

 in those which, like most fishes, and many granivorous birds, 

 swallow their prey without mastication. In fishes, especially, 

 the taste is very imperfect, as is proved by their readily swal- 

 lowing artificial bait. It is probable that they are guided in 

 the choice of their prey by sight, rather than by taste or smell. 



173. Some of the inferior animals select their food with 

 no little discernment. Thus, flies will always select the sugary 

 portions of bodies. Some of the mollusca, as the snails, for 

 example, are particularly dainty in the choice of their food. In 

 general, taste is but imperfectly developed, except in mam- 

 mals, and they are the only animals which appear to enjoy the 

 flavour of their food. With man this sense, like others, may be 

 greatly improved by exercise ; and it is capable of being brought 

 to a high degree of delicacy. 



5. OF TOUCH. 



174. The sense of TOUCH is merely a peculiar* manifesta- 

 tion of the general sensibility, seated in the skin, and depend- 

 ent upon the nerves of sensation which expand over the surface 

 of the body. By the aid of this general sensibility, we learn 

 whether a body is hot or cold, wet or dry. We may also, by 

 simple contact, gain, to a certain extent, an idea of the form 

 and consistence of a body, as, for example, whether it be sharp 

 or blunt, soft or hard. 



175. This faculty resides more especially in the hand, 

 which is not only endowed with a more delicate tact, but, 

 owing to the disposition of the fingers, and the opposition of 

 the thumb to the others, is capable of so moulding itself 

 around objects, as to multiply the points of contact. Hence 



