MOVEMENTS OF THE VOCAL CORDS 



487 



is depressed and brought over the vocal cords, figure 349. The epiglottis, 

 by being somewhat pressed down so as to cover the superior cavity of the lar- 

 ynx, serves to render the notes deeper in tone and at the same time somewhat 

 duller, just as covering the end of a short tube placed in front of caoutchouc 

 tongues lowers the tone. In no other respect does the epiglottis appear to have 

 any effect in modifying the vocal sounds. 



The degree of approximation of the vocal cords also usually corresponds 

 with the height of the note produced; but probably not always, for the width 



FIG. 



48. Three Laryngoscopic Views of the Superior Aperture of the Larynx and Surrounding 



, in easy and quiet inhalation 



r IG. 348. Three i^aryngoscopic Views ot tne superior Aperture or t) 

 Parts. A, The glottis during the emission of a high note in singing; B, i 



of air; C, in the state of the widest possible dilatation, as in inhaling a very deep breath. The 

 diagrams A', B' , and C , show in horizontal sections of the glottis the position of the vocal ligaments 

 and arytenoid cartilages in the three several states represented in the other figures. In all the 

 figures, so far as marked, the letters indicate the parts as follows, viz.: /, the base of the tongue; 

 e, the upper free part of the epiglottis; <?', the tubercle or cushion of the epiglottis; ph, part of the 

 anterior wall of the pharynx behind the larynx; in the margin of the aryteno-epiglottidean fold 

 w, the swelling of the membrane caused by the cartilages of Wrisberg; s, that of the cartilages 

 of Santorini; a, the tip or summit of the arytenoi.l cartilages; cv, the true vocal cords or lips of 

 the rima glottidis; cvs, the superior or false vocal cords; between them the ventricle of the 

 larynx; inC, tr is placed on the anterior wall of the receding trachea, and b indicates the com- 

 mencement of the two bronchi beyond the bifurcation which may be brought into view in this 

 state of extreme dilatation. (Quain, after Czermak.) 



of the aperture has no essential influence on the pitch of the note, as long as the 

 vocal cords have the same tension; only with a wide aperture the tone is more 

 difficult to produce and is less perfect, the rushing of the air through the aper- 

 ture being heard at the same time. 



