THE TONGUE. 



451 



papillae filiformes measure 1J-2 lines, we have the lingua hirsuta or 

 villosa, which is not uncommon in various disorders; and at length forms 

 may be produced, in which the tongue looks as if it were covered with 

 hairs, 4-6 lines long. 2. The papillse filiformes possess very small 

 epithelial processes, or none at all, and are hardly distinguishable from 

 the smaller p. fungiformes. 3. The papillce filiformes do not exist as 

 special elevations, but are imbedded in a general epithelial investment of 

 the dorsum of the tongue. Tongues may be observed, particularly in 

 old people, which, without being furred, in some spots or over a large 

 extent, present no papilla at all, but have either a perfectly smooth 

 surface, or exhibit only a few linear elevations, corresponding with the 

 rows of papillae which would, otherwise, exist there. In these places we 

 find the epithelium more developed, and beneath it small papillae, more 

 of the ordinary form. Tongues which, with better developed papillae 

 present a smooth surface, are again different from these ; here the smooth 

 or cracked surface is produced by the papillae being glued together by 

 superabundant epithelium, mucus, blood, pus-corpuscles, and mucedi- 

 nous or yeast-like fungi. 4. The epithelial processes of the filiform 

 papillce are covered with mucedinous fungi. Every microscopist is 

 doubtless acquainted with brownish, elongated bodies (0-12-0-24 of a 

 line in length, 0-04-0-08 of a line in breadth), consisting of a dark axis 



Fig. 176. 



and a finely granular cortex, from the coating of the tongue. The 

 centre of these bodies only is composed of cornified epithelial cells, 



FIG. 176. A mass of epithelial cells covered with the granular matrix of the fungus, 6, 

 from which a luxuriant growth of mucedinous filaments, c, proceeds; magnified 350 dia- 

 meters. From Man. 



