TASTE-BUDS OF THE TONGUE. 119 



themselves do not project much above the surrounding sur- 

 face, but are depressed. 



Scattered about in the epithelial covering of the sides of the 

 furrow are numerous taste-buds or taste-goblets, oval bodies 

 made up of modified epithelium and containing the terminals 

 of the nerves for the special sense of taste. 



The serous glands of Ebner open into the bottom of the 

 furrows, their watery secretions apparently aiding the solu- 

 tion and dissemination of substances acting on the taste-termi- 

 nals. 



The foliate papillae consist of a few parallel folds of the 

 mucous membrane on each side of the base of the tongue, 

 forming alternate ridges and furrows rather than papilla?. 

 They are better developed in some of the other mammals, as 

 the rabbit, than in man. The sides of their furrows contain 

 taste-buds. 



The taste-buds are terminals for the special sense of taste, 

 and occur in the sides of the furrows of the circumvallate 

 and foliate papillae, with a few scattered about in the epithe- 

 lial layer of the base of the tongue, the lingual surface of the 

 epiglottis, and the soft palate. They are oval or egg-shaped 

 bodies, with the long axis extending through the entire thick- 

 ness of the epithelial layer, perpendicular or slightly oblique 

 to the surface. They are made up of two kinds of modified 

 epithelial cells, the external cortical cells, and the internal 

 gustatory cells. The outer or cortical cells, also variously 

 called protective, sustentacular, supporting, and tegmental 

 cells, are long, slender, flattened, and fusiform cells, each 

 with a prominent nucleus near its middle. 



These cells are arranged longitudinally so as to form an 

 oval body or covering for the gustatory celte, which lie in the 

 axis of the taste-bud. The latter are very slender linear 

 neuro-epithelium cells, with large nuclei near their middle 

 causing a bulging at that point. They extend the entire 

 length of the taste-bud, surrounded by the cortical cells. 

 Their outer ends terminate in fine hairs, reaching the surface 

 of the mucous membrane through a minute opening or pore 

 at the apex of the taste-bud ; their inner ends are slender or 

 branched, and are supposed to communicate with fibres of the 

 special nerves of taste. 



