CHAPTER XXXI. 

 TASTE AND SMELL. 



SENSE OF TASTE. 



NEXT to the sense of touch, which is distributed more or less 

 over the whole cutaneous surface, taste is the least localized 

 anatomically. Though confined to the cavity of the mouth, its 

 more accurate limitations are not easily fixed. The point, sides, 

 and posterior part of the dorsura of the tongue can most accu- 

 rately appreciate tastes ; and probably parts of the palate also 

 have the power, but in a much less degree. Indeed, though "the 

 palate " is often spoken of as if it were the seat of taste, it really 

 enjoys this function in an insignificant degree when compared 

 with the tongue. 



The power of being stimulated by various tastes is not re- 

 stricted to the terminals of any one nerve, but is shared by some 

 of those of at least three trunks, which also transmit impulses 

 arising from other forms of stimulation. The glosso-pharyngeal 

 division of the eighth pair sends branches to the posterior part of 

 the tongue, which are no doubt connected with the special taste 

 organs. The lingual branches of the fifth commonly called the 

 gustatory nerves have also terminals capable of being excited 

 by taste, and probably some fibres of the chorda tympani are also 

 employed in this function. 



In the furrows around the circuravallate papillae, and also, but 

 more sparsely, on the sides of the fungiform papillae of the tongue, 

 are found peculiar organs called " taste-buds" or " taste-goblets." 

 They are imbedded in the stratified epithelium, with the cells of 

 which their outer layers are intimately connected. They are flask- 

 shaped bodies, composed of a concentric series of flattened cells 

 pinched together at the base and at the free surface, where they 

 seem to inclose a kind of orifice. Near the centre the flattened 



