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MANUAL OF PHYSIOLOGY. 



they are made up. The relation of the glosso-pharyngeal nerves 

 to these taste-buds has been shown by the fact that in the rabbit 

 (in which animal they are crowded together in a special organ, 

 so as to be easily found) they degenerate, and in a few months 

 disappear, after one of these nerves has been cut. 



The genuine taste sensations are very few. Much of what we 

 commonly call taste depends almost exclusively upon the smell 



Section through depression between two circumvallate papillae, showing 

 taste-buds. (Cadiat.) a, fibrous tissue of papilla ; d and c, epithelial cov- 

 ering of papilla; b, taste-buds. On the right, a, 6 show the separate cells 

 of a taste-bud. 



of the substance, and we habitually confuse the impressions de- 

 rived from these two senses.* The different tastes have been 

 divided into four, viz., sweet, sour, bitter, and salt, under some 



* Many of the comestibles, the taste of which we most prize, have really 

 no taste, but only a smell which we habitually confound with taste, having 

 mingled the experience obtained from the two senses. Thus, if the draft 

 of air be carefully excluded from the nose, wine, onion, etc., may easily be 

 proved to have no taste. Hence the familiar rule of holding the nose 

 adopted in taking "bad-tasting" medicine. 



