ANATOMY OF THE RESPIRATORY ORGANS 



133 



The Larynx. This lies in front of the esophagus, its 

 upper opening communicating with the middle pharynx. It 

 is composed of four cartilages and the muscles and liga- 

 ments which hold them together. The cartilages keep its 

 lumen constantly open, while the muscles effect movements 

 concerned in deglutition, respiration and phonation. The 

 cartilages are the thyroid, cricoid and two arytenoids. The 



The wind 

 bronchi, whic 



FIG. 47. Diagram of the respiratory organs. 



pipe leading down from the larynx is seen to branch into two large 

 lich subdivide after they enter their respective lungs. (Yeo.) 



two alae of the thyroid meet at an acute angle in front to 

 form the Adam's apple. The cricoid is at the lower end of 

 the larynx, completely surrounding it. The arytenoids are 

 movable and rest upon the back of the cricoid. (Fig. 48.) 



The vocal cords, two ligamentous bands covered by a thin 

 layer of mucous membrane, stretch antero-posteriorly across 

 the upper end of the larynx, while the false vocal cords, 

 having nothing to do with phonation, and pinker in color, are 



