TONGUE PAPILLAE. 



467 



According to Treviranus and Gottsche, the ultimate terminations of the 

 filaments assume the form of papillae. 



The Arteries of the labyrinth are derived principally from the auditory 

 branch of the superior cerebellar artery. 



O RGAN OF TASTE. 



The Tongue is composed of muscular fibres, which are distributed in 

 layers arranged in various directions : thus, some are disposed longitudi- 

 nally ; others transversely ; others, again, obliquely and vertically. Between 

 the muscular fibres is a considerable quantity of adipose substance. 



The tongue is connected, posteriorly, with the os hyoides by muscular 

 attachment ; and to the epiglottis by mucous membrane, which forms the 

 three folds called frana epiglottidis. On either side it is held in connex- 

 ion with the lower jaw by mucous membrane, and in front a fold of that 

 membrane, which is named franum lingua, is formed beneath its under 

 surface. 



The surface of the tongue is covered by a dense layer analogous to the 

 corium of the skin, which gives support to papillae. A raphv marks the 

 middle line of the organ, and divides it into symmetrical halves. 



The Papilla of the tongue are the 



Papillae circumvallatse, 

 Papillae conicse, 

 Papillae filiformes, 

 Papillae fungiformes. 



The Papilla circumvallata (p. lenticulares) are 

 of large size, and from fifteen to twenty in number. 

 They are situated on the dorsum of the tongue, 

 near its root, and form a row on each side, which 

 meets its fellow at the middle line, like the two 

 branches of the letter A. Each papilla resembles 

 a cone, attached by its apex to ^he bottom of a 

 cup-shaped depression : hence they are also named 

 papillae calyciformes. This cup-shaped cavity forms 

 a land of fossa around the papilla, whence their 

 name circumvallata. At the meeting of the two 

 rows of these papillae upon the middle of the root 

 of the tongue, is a deep mucous follicle cabled for- 

 amen cacum. 



The Papilla conica and filiformes cover the 

 whole surface of the tongue in front of the circum- 

 vallatae, but are most abundant towards its anterior 

 part. They are conical and filiform in shape, and 

 many of them are pierced at the extremity by a 

 minute aperture. Hence, they may be regarded as 



* The tongue with its papillae. 1. The raphe. which in some tongues bifurcates on 

 the dorsum of the organ, as in the figure. 2, 2. The lobes of the tongue. The rounded 

 eminences on this part of the organ, and near its tip are the papilla? fungiformes. The 

 smaller papillae, among which the former are dispersed, are the papilla? conica? and 

 filiformes. 3. The tip of the tongue. 4. 4. Its sides, on which are seen the lamellated 

 and fringed papilla). 5, 5. The A-shaped row of papilla circumvallatte. 6. The fora 

 men caecum. 7. The mucous glands of the root of the tongue. 8. The epiglottis. 9, 9. 

 The frsena epiglottidis. 10, 10. The greater cornua of the os hyoides. 



Fig. 207.* 



