1284 



A MANUAL OF ANATOMY 



which are known as the compressor saccuhs laryngis or Hilton's 

 muscle. 



The lower compartment of the larynx is compressed from side 

 to side above, but becomes circular inferiorly, where it opens into 

 the trachea. 



Vocal Cords. — ^These are arranged in two pairs, laterally disposed, 

 called false and true, or superior and inferior. 



The superior or false vocal cords are two folds of mucous mem- 

 brane, which extend at either side from the receding angle of the 

 thyroid cartilage immediately below the attachment of the thyro- 

 epiglottidean ligament to the antero-external surface of the 

 arytenoid cartilage, a little above the vocal process. Each contains 



Hyoid Bone (in section)- 

 Thyro-hyoid Membrane. 



Thyroid Cartilage.. 

 True Vocal Cord. 



Crico-thyroid MembraneL-ir-' 



Cricoid Cartilage . 

 (anterior part) 



_ -i .Epiglottis 



.False Vocal Cord 

 .Ventricle 



..Arytenoid Muscle (in section) 

 .Arytenoid Cartilage 



.Cricoid Cartilage 

 (posterior part) 



Trachea 



Fig. 532. — Sagittal Section of the Larynx and Trachea, showing 

 THE Vocal Cords and Ventricle of the Right Side. 



some fibrous tissue forming the superior thyro- arytenoid ligament. 

 The false vocal cords are widely separated from each other by an 

 interval known as the false glottis, so that the true vocal cords are 

 visible on looking into the larynx from above. 



The inferior or true vocal cords are concerned in the production 

 of the voice. They are prominent folds at either side, which are 

 rather less than an inch in length, and extend from the receding 

 angle of the thyroid cartilage to the vocal process of each arytenoid 

 cartilage. Each cord consists of the inferior thyro-arytenoid liga- 

 ment, which is continuous with the upper part of the expanded 

 lateral portion of the crico-thyroid membrane, and is composed of 

 yellow elastic tissue. The mucous membrane covering the cord 

 is thin, and firmly adherent to the elastic tissue of the ligament, 



