626 



THE VALVULAR ACTION OF THE LARYNX. 



would appear that they have not received the attention they 

 deserve. Wyllie points out that Czermak was probably de- 

 ceived in regard to the second factor in the closure of the 

 glottis. 



Czermak thought that the superior vocal cords approach the 

 inferior, so as to obliterate the ventricles of Morgagni, at the 

 same time that they also meet in the median line. 



As Wyllie points out, and as reference to the accompanying 

 Fig. 215 w411 show, it is impossible to say anything with certainty 

 regarding the condition of the entrance to the ventricles of 



Fig. 215.— Anterior half of a transverse vertical section through the larynx 

 near its middle. (From Allen Thomson in Quain^s Anatomy.) 1, Upper 

 division of the laryngeal cavity ; 2, central portion ; 3, lower division con- 

 tinued into 4, part of the trachea ; e, the free part of the epigiottis ; c', its 

 cushion ; A, the divided great cornua of the hyoid bone ; ht, thyro-hyoid 

 membrane ; t, cut surface of the divided thyroid cartilage ; c, that of the 

 cricoid cartilage ; r, first ring of the trachea ; ta^ thyro-arytenoid muscle ; 

 vl, thyro-arytenoid ligament in the true vocal cord covered by mucous 

 membrane at the rima glottidis ; *, the ventricle, above this the superior 

 or false cords j / the sacculus or pouch opened on the right side. 



