38 THE LARYNX AND TRACHEA, BY E. VERSON. 



a broad basis where it is connected with the capsule, whilst it 

 becomes attenuated as it advances internally. It is usually com- 

 posed of firm tense fibrous tissue containing a small number of 

 large cartilage cells, but is not, like the rest of the internal 

 surface of the capsule of the joint, invested by epithelium. 



The capsule of the crico-thyroid articulation is principally 

 composed of connective tissue which is prolonged over nearly 

 the whole extent of the articular surface of the cricoid carti- 

 lage. Cartilage cells are disseminated throughout the tissue of 

 the capsule. The accessory ligaments of this joint are rela- 

 tively poor in .elastic tissue. 



SOFT PARTS. 



The epiglottis is invested by a mucous membrane which, 

 especially near the apex, is characterized by its delicacy and by 

 its being comparatively loosely connected with the perichon- 

 drium ; it contains numerous longitudinal elastic fibres, between 

 which are spheroidal corpuscles with one or many nuclei, that 

 are especially abundant at the sides of the bloodvessels and 

 immediately subjacent to the epithelium. The free surface of 

 the mucous membrane on the posterior surface of the epiglottis 

 appears in transverse sections limited towards the epithelium 

 by a sharply defined straight line, whilst anteriorly the contour 

 line of the membrane is sinuous, and presents papillae that pro- 

 ject into the epithelium, of O7 0'18 of a millimeter in length, 

 the larger examples of which terminate in two or even three 

 points, and contain beautiful vascular loops, Inferiorly towards 

 the entrance into the trachea the mucous membrane becomes 

 thicker, is more sharply differentiated from the loose sub- 

 mucous tissue, and from this point downwards preserves a 

 thickness of 1< 0'15 of a millimeter, becoming somewhat 

 thickened, however, in some instances, at the upper or false 

 vocal cord. 



The epithelium of the anterior surface of the epiglottis con- 

 sists of well-marked laminated pavement cells, and is from 0'2 

 to 0'3 of a millimeter thick. It is much thinner posteriorly, 

 only amounting to 0*06 O'l of a millimeter. The deepest 

 layer consists of delicate columnar cells arranged like pali- 

 sades ; above these is a layer of more rounded or polygonal 



