ORGAN OF TASTE. 249 



When we examine the structure of the mucous membrane 

 of the mouth, tongue, and palate, we find that the upper sur- 

 face of the tongue presents numerous papillae, called, in con- 

 tradistinction to the filiform papillae, fungiform and circum- 

 vallate. These are not found on its under surface, nor any- 

 where except on the superior surface. It is pretty well 

 established, particularly since the recent very elaborate ob- 

 servations of Dr. Camerer, of "Wiirttemberg, that the cir- 

 cumvallate and fungiform papillae alone are the organs of 

 taste. This experimenter, by the application of solutions 

 to different parts through fine glass tubes, concluded that 

 the parts around a papilla have no gustatory sensibility, but 

 that different savors can be distinguished when a single 

 papilla is touched. 1 These observations give a new im- 

 portance to the peculiar papillae of the tongue, and we 

 therefore present a description of their arrangement and 

 structure. 



In Fig. 20, which represents the dorsal surface of the 

 tongue, the large, circumvallate papillae, which usually num- 

 ber from seven to twelve, are seen in the form of a Y, oc- 

 cupying the base of the tongue. The fungiform papillae are 

 scattered over the surface, but are most numerous at the point 

 and near the borders. Both of these varieties of papillae are 

 distinguishable by the naked eye. 



The circumvallate papillae are simply enlarged fungiform 

 papillae, each one surrounded by a circular ridge, or wall, 

 and covered by numerous small, secondary papillae. The 

 fungiform papillae have a short, thick pedicle and enlarged, 

 rounded extremities. According to Sappey, from one hun- 

 dred and fifty to two hundred of these can easily be counted. 3 

 They, also, present secondary papillae on their surface. When 

 the mucous membrane of the tongue is examined with a low 

 magnifying power, particularly after maceration in acetic or 



1 CAMERER, Ueber die Abhangigkeit des GeschmacTcsinns von der gerdzten Stella 

 der MundhoMe. Zeitechrift fur Biologie, Miinchen, 1870, Bd. vi., S. 440. 

 8 SAPPEY, Traite d'anatomie, Paris, 1871, tome iii., p. 618. 



