SENSE OF TASTE. 



169 



An upright section of one of the papillae of the tongue very greatly 

 magnified, and split open, to show the nerves (engraved white) and the 

 blood-vessels (black.) 



5. The process of taste, then, is as follows : When a 

 fluid is taken into the mouth, these papillae dilate and erect 

 themselves, being endowed with the property of adapting 

 themselves to the active or passive condition of the sense of 

 tasteO If a solid portion of food is received, it is first touch- 

 ed by the tip of the tongue and brought into close contact 

 with the papillae ; when if it be dry or solid, it is carried to 

 the back of the tongue and moistened with saliva, which 

 thus becoming impregnated with its flavour, and flowing 

 over the sides of the tongue, gives to the papillae a percep- 

 tion of the savoury juices. The saliva, or spittle, it should 

 "be recollected, is secreted by the parotid and other salivary 



15 



