692 THE EAE 



columnar ciliated variety, continuous with, and similar to the respiratory 

 epithelium of the nasopharynx, together with a fibrous membrana 

 propria which is loosely connected with the surrounding bony, car- 

 tilaginous, and muscular walls. The lower portions of the tube are 

 richly supplied with mucus-secreting, tubulo-acinar glands, and toward 



FIG. 577. TRANSECTION OF THE EUSTACHIAN TUBE; DIAGRAMMATIC. 



1, cartilaginous plate; 2, lateral or hooked end of the cartilage; 8, ' dilator tubss * 

 (tensor palati); 4, levator palati; 5, fibrocartilage at the base of the skull; 6 and 7, 

 mucous glands; 8, adipose tissue; 9, 11, lumen of the tube; 10, 12, connective tissue. 

 Low magnification. (After Riidinger.) 



its pharyngeal end the mucosa is much infiltrated with lymphoid tissue, 

 thus forming the tubal tonsil of Gerlach. 



The cartilage of the auditory tube is firmly adherent to the bony wall. 

 At the point of attachment it has a hyaline structure, the fibers of 

 the perichondrium penetrating only the surface of the cartilaginous 

 plate. Lower down the cartilage becomes infiltrated with fibers and 

 conforms to the typical elastic variety. Like the cartilage of the auricle 

 it is rich in cellular elements. Its transection presents a peculiar hook- 

 like form, by means of which the posterior surface, the superior margin, 

 and the upper portion of the anterior surface are invested by cartilage, 



