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THE DIGESTIVE SYSTEM 



in man, but are well developed in the rabbit and certain other rodents. 

 They contain numerous taste buds. In the lymphoid area also, at the 

 anterior lateral margins, are a group of low irregularly disposed mucous 

 folds, the so-called lenticular papillce. 



FlG. 322. ClRCUMVALLATE PAPILLA OF HUMAN TONGUE. X55. 



Mucous and SEROUS GLANDS occur in the deeper portion of the 

 corium of the tongue and among its muscle bundles; they open upon 

 its epithelial surface between the papillae. These glands are most 

 abundant at the base of the organ but are also found along its margins 

 as far forward as the tip, where a pair of small tubulo-acinar sero- 

 mucous glands lie on either side of the median septum and open upon 

 the ventral surface of the tongue. These are the anterior lingual 



