CHAPTER XIV. 



SENSE OP TASTE. 



1. THE sense of taste is allied to that of smell and touch, 

 as it requires the immediate contact of the body with the 

 organ where the sense resides) (The quality of bodies, 

 which it teaches us, is called sapidity. The superior surface 

 of the tongue is the chief organ of taste ; though;the general 

 lining of the mouth and the upper part of the throat partici- 

 pate in the function^ fThe tongue is chiefly composed of 

 muscular fibres, running almost in every direction ; conse- 

 quently it possesses great versatility of motion, and can be 

 moulded into a great variety of shapes. It may be con- 

 sidered as a double organ, as it is formed of two symmetrical 

 halves, whose boundaries are marked by a slight groove in 

 its upper surface ; dividing it into right and left. From 

 this groove a membranous partition extends down through 

 its centre, and is attached to the froenum or bridle beneath. 

 The tongue is not only the organ of taste but also of articu- 

 lation, and also aids in mastication and deglutition^ 



2. The tongue is abundantly supplied with blood-vessels ; 

 and its nerves, as we have seen, are supplied from three 

 sources. There has existed great difference of opinion 

 among physiologists, as to which of these three is the special 

 nerve of taste. General opinion now holds the ffth, as the 

 proper nerve of taste, as well as of sensibility ; the ninth, as 

 that of voluntary motion ; and the eighth, as the means 

 whereby the organ is brought into association with the 

 throat, gullet, larynx, &cJ /jD r * Elliotson, however, and some 

 others, think that the glosso-pharyngeal is the nerve of 

 taste. 



3*. When we examine the surface of the tongue, we find 

 it thickly studded with fine papillae, or viJli, giving the organ 



