NORMAL HISTOLOGY. 



FIG. 194. 



The nerves supplying the mucous membrane the glosso-pharyn- 

 geal and the lingual branch of the trifacial end either beneath the 

 epithelium in the usual manner, or in close relation with the organs 

 of special sense the taste-buds. Numerous microscopic ganglia also 

 occur along their course, especially in connection with the fibres of 

 the glosso-pharyngeal nerve. 



THE TONSILS. 



The tonsils represent compound lymphatic glands, while con- 

 siderable variation exists as to form and size, each organ consisting 

 of an aggregation of from ten to eighteen lymph-follicles, closely 



resembling those found at the root of 

 the tongue embedded within the sur- 

 rounding diffuse adenoid tissue. 

 The entire mass is separated from the 

 adjacent structures on the attached 

 borders by a fibrous capsule, and is 

 covered with a reflection of the oral 

 epithelium on the mucous surface, in- 

 cluding the deep central pit on which 

 the lymph-follicles abut. The epi- 

 thelium covering the folds and de- 

 pressions of these surfaces is com- 

 pletely infiltrated with lymphoid cells, 

 so that the demarcation between the 

 epithelium and the subjacent adenoid 

 tissue is often obscure. 



Numerous mucous glands occupy 

 the immediate vicinity of the tonsils, 

 into the crypts of which the glands 

 pour their secretion to mingle with 



Section of child s tonsil, showing the r .,,. i 1 i j 



the shed epithelium and lymphoid 

 cells occupying the recesses. Great 

 numbers of the escaped lymphoid 

 cells pass into the oral cavity to become salivary corpuscles, of 

 which the tonsils are a most important source. 



Blood-vessels and lymphatics occur in large numbers within 

 the adenoid tissue ; venous and lymphatic plexuses surround the 

 organ receiving the radicles issuing from the interior. Lymph- 

 channels encircle the individual follicles, and afterwards communicate 

 with the larger peripheral vessels. 



Regarding the ultimate distribution of the nerves little is defi- 

 nitely known ; fibres have been traced into the subepithelial 

 plexus. 



details of the epithelium and part of the 

 lymphoid tissue from preceding figure 

 under higher amplification. 



