278 THE SENSORIAL FUNCTIONS. 



many have the nose prolonged and flexible, apparently with 

 this view. This is the case with the Shrew and the Mole, 

 which are burrowing animals, and still more remarkably 

 with the Pachydermata, where this greater sensibility of the 

 parts about the face seems to have been bestowed as some 

 compensation for the general obtuseness of feeling resulting 

 from the tliickness of the hide which covers the rest of the 

 body. Thus, the Rhinoceros has a soft, hook-shaped exten- 

 sion of the upper lip, which is always kept moist, in order 

 to preserve its sensibility as an organ of touch. The Hog 

 has the end of the nose also constructed for feeling; though 

 it is not so well calculated for distinguishing the form of ob- 

 jects, as where the organ is prolonged in the form of a snout, 

 which it is in the Tapir, and in a still higher degree in the 

 admirably constructed proboscis of the Elephant, which, as 

 an organ, both of prehension and of touch, forms the nearest 

 approach to the perfect structure of the human hand. 



The Lion, Tiger, Cat, and other animals of the genus Fe- 

 lls, have whiskers, endowed at their roots with a particular 

 sensibility, from being largely supplied with nerves. The 

 same is the case with the whiskers of the Seal. 



The prehensile tails of the American monkeys are doubt- 

 less fitted to convey accurate perceptions of touch, as well 

 as the feet and hands: as may be inferred from the great size 

 of the nervous papillae, and the thinness of the cuticle of 

 those parts. 



The sense of touch attains its greatest degree of excellence 

 in the human hand, in which it is associated with the most 

 perfect of all instruments of prehension. But as the struc- 

 ture and functions of this organ are the exclusive subjects of 

 another of these treatises, I shall refrain from any farther 

 remarks respecting them. 



