192 



ELEMENTS OF MAMMALIAN ANATOMY 



fibrous tissue from the cartilage the larynx is seen to be com- 

 posed of five pieces: the epiglottis, thyroid cartilage, two ary- 

 tenoid cartilages, and the cricoid cartilage (Fig. 21). The 

 epiglottis is the small triangular cartilage that closes the glottis 

 when food passes into the esophagus (Fig. 62). The thyreoid 

 cartilage constitutes the largest part of the larynx. In man it 

 forms the prominence known as Adam's apple. Dorsally the 





Fig. 93. — Diagrammatic Transverse Section of the Chest. 

 ao. Aorta; br, bronchus; crd, spinal cord; esoph, esophagus; hd, head of rib; 

 pa, parietal pleura; pc, cavity of the pleura; sp, spinous process; st, sternum; 

 tb, tubercle of rib; tr, transverse process; vp, visceral pleura; /, thoracic duct; 

 n, sympathetic nerve cord; as, azygos vein; trc, trachea; v, pulmonary veins. 



two halves of the thyreoid cartilage are separated, each pro- 

 jecting craniad into a process known as a cornii. The arytenoid 

 cartilages are the two small paired pieces caudad to the thy- 

 reoid, on the dorsal side. The cricoid cartilage forms a com- 

 plete ring at the caudal end of the larynx (Fig. 21). 



There are a number of ligaments connecting the various 

 parts of the larynx, the most important of which are the vocal 

 cords. These are of two kinds — true and false. They are 

 best demonstrated by dividing the larynx, sagittally. The 

 superior or false vocal cords are the two superior thyreo-ary- 



