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The undissected vocal fold of the right side should be examined 

 again ; the laryngeal ventricle and appendix should be explored, 

 and their precise connections and extent determined. When 

 the dissector has satisfied himself about those points he can 

 proceed to display the vessels and nerves of the larynx. The 

 superior laryngeal artery and the internal laryngeal nerve reach 

 the pharynx by piercing the lateral thin part of the thyreo-hyoid 

 membrane, and they descend, along the lateral wall of the 

 recessus piriformis, to the larynx. By applying traction to the 

 nerve, and at the same time dividing the mucous membrane 

 upon the medial surface of the thyreo-hyoid membrane, the 

 dissector can easily find the nerve and artery. As the branches 

 into which they divide are followed, the mucous membrane 

 must be gradually removed from the wall of the larynx. The 

 inferior laryngeal artery and nerve enter from below and proceed 

 upwards, under cover of the lamina of the thyreoid cartilage. 

 They can be satisfactorily displayed only by the removal of that 

 piece of cartilage, but the dissector is not recommended to adopt 

 the method suggested unless another larynx is available for the 

 examination of the cartilages and joints. If the thyreoid cartilage 

 is drawn laterally the more important branches can be studied. 



Ramus Interims Nervi Laryngei Superioris. In the dissec- 

 tion of the neck the internal laryngeal nerve of each side was 

 seen springing from the superior laryngeal branch of the 

 corresponding vagus. It is a sensory nerve, and its branches 

 are distributed chiefly to the mucous membrane of the 

 larynx. After piercing of the thyreo-hyoid men.brane, it 

 divides into three branches. The uppermost of the three 

 sends filaments to the ary-epiglottic fold, to the mucous 

 membrane which covers the epiglottis, to the folds anterior 

 to it, and to the lower and middle part of the back of 

 the tongue. The twigs which go to the epiglottis ramify 

 on its posterior surface, but many of them pierce the cartilage 

 to reach the mucous membrane on its anterior surface. The 

 middle branch of the internal laryngeal nerve breaks up into 

 filaments which are given to the mucous membrane lining 

 the side wall of the larynx. The lowest branch descends and 

 gives filaments to the mucous membrane on the lateral and 

 posterior aspects of the arytaenoid and cricoid cartilages. 

 It also gives off a fairly large twig which runs downwards 

 upon the posterior aspect of the cricoid cartilage to join the 

 laryngeal branch of the recurrent nerve. 



Nervus Recurrens. Each recurrent nerve has previously 

 been seen arising from the corresponding vagus, and it has 

 been traced, in the neck, up to the point where it disappears 

 under cover of the lower border of the inferior constrictor 

 muscle and becomes the inferior laryngeal nerve, which ascends 



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