THE LAEYNX 



301 



are many small tubulo-acinar mucous glands. These are most abun- 

 dant in the region of the ventricle and the false vocal cords. Jji_this 

 region also there is much diffuse lymphoid tissue, and the lateral and 

 dorsal wall contains several solitary nodules which are so constant in 

 their appearance as to warrant designating them 'laryngeal tonsil' 

 (Frankel). Occasionally, however, 

 lymph nodules are not present in the 

 mucous membrane of the human 

 larynx. The deeper portion of the 

 tunica propria in certain parts, e.g., in 

 the false vocal cords, contains a few 

 striped muscle fibers in addition to those 

 of the named muscles of the larynx. The 

 false vocal cords and the aryteno-epi- 

 glottic folds contain loose fibrous tissue 

 and frequently much fat. 



The true vocal cords are formed by 

 dense bands of elastic and a few col- 

 lagenous fibers which are covered by a 

 mucosa clothed with stratified squamous 

 epithelium. Their free margin is sharp- 

 ly defined; at their attached margin, 

 however, they blend indistinctly with 

 the tunica propria. The free margin of 

 the vocal cords has no connective tissue 

 papillae on the surface of the tunica 

 propria, but toward the trachea super- 

 ficial papillae of connective tissue pro- 

 ject into the deeper surface of the 

 stratified epithelium. 



The mucous membrane of the larynx 

 is freely supplied with blood-vessels 



and lymphatics. The latter terminate in the deep cervical lymph 

 nodes. The nerve fibers form an abundant plexus in the laryngeal 

 mucosa, from which motor fibers are distributed to the muscles and 

 sensory fibers to the epithelium. The latter end in fine fibrils between the 

 cells of the lining epithelium. In the stratified squamous epithelium, 

 especially that of the epiglottis, small taste buds are also found; none, 

 however, occur on the vocal cords. 



FIG. 286. A VERTICAL SECTION 

 THROUGH THE LATERAL WALL 

 OF THE HUMAN LARYNX. 



a, cartilage; b, laryngeal mucosa, 

 clothed with ciliated epithelium; 

 c, transection of the vocal cord, in 

 this region the mucosa is clothed 

 with stratified epithelium; d, ducts 

 of mucous glands; e, lymphoid 

 nodule; /, muscle; g, mucous 

 glands; h, submucosa; i, blood- 

 vessel; V, ventricle of the larynx. 

 Hematein and eosin. Photo. X 8. 



