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HANDBOOK OF PHYSIOLOGY. 



posterior surface of the epiglottis, and in several other situations in the 

 laryngeal mucous membrane. 



The Trachea and Bronchial Tubes. The trachea or wind-pipe 

 extends from the cricoid cartilage, which is on a level with the fifth cer- 



FIG. 144. 

 Fio. 144. Outline showing 



FIG. 145. 



44. Outline showing the general form of the larynx, trachea, and bronchi, as seen from 

 before, h, the great cornu of the hyoid bone; e, epiglottis; t, superior, and V inferior cornu of the 

 thyroid cartilage ; c, middle of the cricoid cartilage ; tr, trachea, showing sixteen cartilaginous rings 

 6, the right, and 6', the left bronchus. CAllen Thomson. > x %. 



FIG. 145. Outline showing the general form of the larnyx, trachea, and bronchi as seen from 

 behind, h, great cornu of the hyoid bone, t, superior, and t\ the inferior cornu of the thyroid 

 cartilage; e, epiglottis; a. points to the back of both the arytenoid cartilages, which are surmounted 

 by thecornicula; c, the middle ridge on the back of the cricoid cartilage; tr, the posterior mem- 

 branous part of the trachea; 6, 6', right and left bronchi. (Allen Thomson.) %. 



vical vertebra, to a point opposite the third dorsal vertebra, where it 

 divides into the two bronchi, one for each lung (Fig. 144). It measures, 

 on an average, four or four and a half inches in length, and from three- 

 quarters of an inch to an inch in diameter. 



