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HANDBOOK OF PHYSIOLOGY. 



than of taste; the latter sense being probably seated especially in the 

 other two varieties of papillae, the circumvallate and the fungiform. 



The epithelium of the tongue is stratified with the upper layers of 

 the squamous kind. It covers every part of the surface; but over the 

 i'ungiform papillae forms a thinner layer than elsewhere. The epithe- 

 lium covering the filiform papillae is extremely dense and thick, and as 

 before mentioned, projects from their sides and summits in the form of 

 long, stiff, hair-like processes (Fig. 372). Many of these processes bear 

 a close resemblance to hairs. Blood-vessels and nerves are supplied 

 freely to the papillae. The nerves in the fungiform and circumvallate 



FIG. 372. Two filiform papillse, one with epithelium, the other without 35/1. d, the substance 

 of the papillae dividing at their upper extremities into secondary papillae; a, artery, and v, vein, di- 

 viding into capillary loops; e, epithelial covering, laminated between the papillse, but extended into 

 hair-like processes, /, from the extremities of the secondary papillae. (From Kolliker, after Todd 

 and Bowman.) 



papillae form a kind of plexus, spreading out brush-wise (Fig. 370), but 

 the exact mode of termination of the nerve-filaments is not certainly 

 known. 



Taste Goblets. In the circumvallate papillae of the tongue of man 

 peculiar structures known as gustatory luds or taste goblets, have been 

 discovered. They are of an oval shape, and consist of a number of 

 closely packed, very narrow and fusiform, cells (gustatory cells'). This 

 central core of gustatory cells is inclosed in a single layer of broader fu- 



