1 66 



THE BIOLOGY OF THE FROG 



CHAP. 



loop, the tracheal process, which is bent backward and 

 serves as a means of attachment for the necks or roots of 



ring. 



Fig. 44. — Respiratory organs of the frog. A, ventral aspect. The right 

 lung, r. lug, has been laid open to show the inner surface. In B the 

 larynx has been cut through the middle, and the right half of the larynx 

 and right lung are seen from the side, ar, arytenoid cartilage ; b. hy, 

 main part of the hyoid ; gl, glottis ; l.tr.c, laryngo-tracheal chamber; 

 p. c. hy, posterior horn of hyoid ; v. cd, vocal cord. (After Howes.) 



the lungs. The arytenoid cartilages are a pair of semilunar 

 valves, which rest upon the cricoid cartilage ; their upper 



CIZ. 



m 



Fig. 45. — Cartilages of the larynx of the frog. A, from above; B, from 

 the side; Ca, arytenoid cartilage; C. Z 1 to C. / 4 , cricoid cartilage; P, 

 expansion of the cricoid; Sp, spinous process of the cricoid; * * *, 

 prominences of the arytenoids. (After Wiedersheim.) 



edges form the lateral margins of the glottis; they afford 



