HEAD. 115- 



last nerve. In the chest the right nerve turns obliquely 

 round the axillary artery to place itself outside the 

 trachea until the root of the bronchia, where it ends ; 

 the left nerve remains attached to the artery, crosses 

 outv^ards the origin of the aorta, and terminates by 

 branches which give rise to the bronchial plexus and 

 oesophageal nerves. Collateral branches : 1 — Branches 

 to the superior cervical ganglion ; 2 — The pharyngeal 

 to the superior face of the pharynx; 3 — The superior 

 laryngeal to the susglottic portion of the larynx ; 4 — 

 Branches to inferior cervical ganglion ; 5 — Inferior 

 laryngeal or recurrent nerves, which rise from the tenth 

 into the thoracic cavity, and run forwards and upwards 

 into the larynx, where they divide into the muscles and 

 mucous membrane of the subglottic portion. Terminal 

 branches : Bronchial plexus going to the mucous mem- 

 brane of the bronchia ; oesophageal, divided into supe- 

 rior and inferior, the last terminating in the walls of 

 the stomach ; the former into the left sac of that organ, 

 and the solar plexus. 



II. Spinal OR ACCESsoRius. — Origin: from the cer- 

 vical marrow, runs upwards and forwards in the verte- 

 bral canal till it reaches the tenth pair, with which it 

 comes out of the cranium. Course : first united to 

 the par vagum, it soon leaves it, runs backwards, passes 

 under the maxillary gland, arrives at the posterior 



