LESSON XXXI. 

 DISSECTION OF THE LARYNX, 



1 . IT is preferable to obtain a fresh larynx of a 

 sheep or an ox from the butcher's; but the 

 spirit-preserved larynx of the dog (Lesson I.) 

 will serve. The larynx will probably be obtained 

 with the upper part of the oesophagus attached, 

 and surrounded by a mass of muscle and con- 

 nective tissue. 



Having slit up the oesophagus lengthways, turn 

 back or cut away the sides and observe the 

 opening into the larynx bounded in front by the 

 epiglottis, at the sides by folds of the mucous 

 membrane, and behind by the large converging 

 yellow crests of the arytenoid cartilages. On 

 looking down into the larynx the opening be- 

 tween the vocal cords, or rima glottidis, may 

 be seen at some depth below. Observe that the 

 mucous membrane of the oesophagus is con- 

 tinuous with that of the larynx. Bend down 

 the epiglottis projecting from the front, upper, 

 edge of the larynx, and note that the passage to 

 the larynx is then quite closed. 



