550 



THE SENSE OF TASTE. 



summit. They also consist of groups of simple papillae, each 

 of which contains in its interior a loop of capillary blood- 

 vessels, and a nerve-fibre. 



FIG. 203. 



Vertical section of the circumvallate papillae (from Kolliker). ij> . A, the papillae ; 

 B, the surrounding wall ; a, the epithelial covering ; &, the nerves of the papilla and 

 wall spreading towards the surface ; c, the secondary papillae. 



Conical or Filiform Papillae. These, which are the most 

 abundant papillae, are scattered over the whole surface of the 

 tongue, but especially over the middle of the dorsum. 



FIG. 204. 



a 



Surface and section of the fungiform papillae (from Kolliker, after Todd and Bow- 

 man.) A, the surface of a fungiform papilla, partially denuded of its epithelium, 3^5. 

 a, epithelium. B, section of a fungiform papilla with the bloodvessels injected ; 

 a, artery ; v, vein ; c, capillary loops of simple papillae in the neighboring structure 

 of the tongue. 



They vary in shape somewhat, but for the most part are 

 conical or filiform, and covered by a thick layer of epidermis, 

 which is arranged over them, either in an imbricated manner, 

 or is prolonged from their surface in the form of fine, stiff 

 projections, hair-like in appearance, and in some instances in 

 structure also (Fig. 205). From their peculiar structure, it 

 seems likely that these papillae have a mechanical function, or 



