VENTRICLE OF GALEN OR MORGAGNI RIMA GLOTTIDIS. 481 



tricle of Morgagni, it will be found to pass much above the supe- 

 rior thyro-arytenoid ligament, into a prolongation of the cavity of 

 Fig. 121.* the ventricle, which extends as high as^the 

 upper margin of the thyroid cartilage, and 

 which has been called by Mr. Hilton, the 

 Sacculus Laryngis. It was pointed out 

 by Morgagni, and has been compared by 

 M. Cruvielhier, from its shape, to a Phry- 

 gian casque. It is apt to escape observation 

 in the healthy state. When death has taken 

 place, from pulmonary emphysema, or lar- 

 yngeal phthisis, I have, on several occasions, found the sac so 

 large as to project considerably above the thyroid cartilage. 

 The ventricle and its sac, appear to be intended for the supply of 

 a lubricating secretion to the vocal chords, which are kept in 

 such constant action, during respiration and phonation. The sur- 

 face of the cavity, is studded with sixty or seventy small follicu- 

 lar glands, which are seated in the submucous tissjue, and give 

 to the mucous membrane, when dissected out, a rough appear- 

 ance. The greater part of these follicles is placed in the sac, 

 and the fluid which they form, is directed upon the rima glottidis, 

 by two small folds of mucous membrane, at the entrance of 

 the sacculus. 



The aperture between the two lower ligaments is called the 

 Rima Glottidis, or Chink of the Glottis; the upper aperture, 

 formed by 4 the fold of the membrane and extending from the 

 epiglottis to the arytenoid cartilages, may be termed Glottis. 



The folds of the membrane forming the upper margin of 

 the glottis is loose and distensible, and is liable in laryngeal 

 inflammation to become oedematous and bag out so as to im- 

 pede respiration to a great extent, and even produce suffoca- 

 tion. 



If the windpipe is divided near the larynx, and the larynx 

 inverted, so that the rima glottidis may be examined from 

 below, the structure appears still more simple: it resembles a 



* Front view of the larynx ; plan of its interior cavity, represented by the 

 lines a c, b b. /s, Superior ligaments of the glottis. U, Inferior ligaments. 



41 



