190 ELEMENTS OF HISTOLOGY. [Chap. xxm. 



the palate, uvula (levator and tensor palati), and the 

 arcus, palato-pharyngeus, and palato-glossus. 



256. The last branches of the arteries break up in 

 a dense capillary network on the surface of the mucosa, 

 and from it loops ascend into the papillae. Of 

 course, fat tissue, glands, and muscular tissue re- 

 ceive their own supply. There is a very rich plexus 

 of veins in the superficial part of the mucosa. They are 

 conspicuous by their size and the thinness of their wall. 



The lymphatics form networks in all layers of the 

 mucosa, including the papillae. The large efferent 

 trunks are situated in the submucosa. The last 

 outrunners of the nerve branches form a plexus of non- 

 medullated fibres in the superficial layer of the mucosa, 

 whence numerous primitive fibrillce ascend into the 

 epithelium to form networks. Meissner's tactile cor- 

 puscles have been found in the papillae of the lips and 

 in those of the tongue. 



257. In the pharynx the relations remain the 

 same, except in the upper or nasal part, where 

 we find numerous places covered with columnar 

 ciliated epithelium. As in the palatine tonsils so 

 also here, the mucosa is infiltrated with diffuse 

 adenoid tissue, and with lymph follicles in great 

 numbers. This forms the pliarynx tonsil of Luschka. 



In the palatine tonsil and in the pharynx tonsil 

 there are numerous crypts leading from the sur- 

 face into the depth. This is due to the folding of 

 the infiltrated mucosa. Such crypts are, in the 

 pharynx, sometimes lined all through with ciliated epi- 

 thelium, although the parts of the free surface around 

 them are covered with stratified pavement epithelium. 



258. The tongue is a fold of the mucous 

 membrane. Its bulk is made up of striped muscular 

 tissue (genio-, hyo-, 'and stylo-glossus ; according to 

 direction : longitudinalis superior and inferior, and 

 transversus linguae). The lower surface is covered 



