3io 



PHYSIOLOGY. 



the sides of the larynx. Under the covering of mucous 

 membrane are ligaments and muscles that may be stretched 

 to various degrees and placed in different positions, accord- 

 ing to the sound that is to be produced. 



The Position of the Vocal Cords. While we are 



quietly breathing, the vocal cords, or bands, lie back, like 

 low ridges, against the side of the larynx, and offer nearly 

 the whole channel of the larynx for the free passage of air 



Tiachca 



FROM RIGHT TO LEFT MEDIAN 



Fig. 94. Longitudinal Sections of the Larynx. 



for breathing purposes. But when we wish to produce 

 vocal sound, the vocal cords are made to stand out farther 

 from the side walls, and interfere with the free passage of 

 the air. In examining the larynx, it is seen that the vocal 

 cords are attached close to each other in front, but that at 

 the back of the larynx they diverge widely (in the position 

 of rest), forming a letter V, with the angle of the V in 

 front, just back of Adam's apple. " When changes in the 

 voice or in breathing are being made, the white glistening 



