334 ELEMENTARY PHYSIOLOGY. [XXXI. 



arytenoid muscle. Cut away its attachment 

 to the lateral portion of the upper margin of the 

 cricoid, and, reflecting it, observe that it passes 

 backwards and upwards from the cricoid to be 

 inserted into the arytenoid cartilage just in front 

 of the insertion of the posterior crico-arytenoid. 



8. Clearing away the fat and connective tissue 

 from the side of the larynx, observe the thyro- 

 arytenoid muscle stretching across from the 

 thyroid in front to the arytenoid behind. Cut it 

 through in the middle and reflect both ends. 

 Note its origin from the angle of the thyroid and 

 its insertion into the lateral surface of the 

 arytenoid in front of the insertion of the lateral 

 crico-arytenoid. 



Remove the muscle altogether, and observe the 

 lateral surface of the arytenoid cartilage. 



9. Cut away on the same side the underlying 

 mucous membrane; the interior, of the larynx 

 will now be laid open. On the opposite side the 

 indistinct vocal cord will be seen passing as a 

 pale band of tissue from the anterior angle of 

 the arytenoid cartilage to the angle of the 

 thyroid. The inner or median surfaces of the 

 arytenoid cartilages will be seen to bound a 

 large oval space, called the respiratory space. 



10. Clear away on one side any muscle or connective 

 tissue still attached to the arytenoid cartilage, 

 and observe more fully its shape, noting par- 

 ticularly the anterior projection or processus 





