452 SPINAL ACCESSORY NERVE. 



nerve and in its distribution, of its sensitive function. The recurrent, 

 or inferior laryngeal nerve, is the proper motor nerve of the larynx, 

 and is distributed to its muscles. 



The Cardiac branches, two or three in number, arise from the pneu- 

 mogastric in the lower part of the neck, and cross the lower part of the 

 common carotid, to communicate with the cardiac branches of the sym- 

 pathetic, and with the great cardiac plexus. 



The Recurrent laryngeal^ or inferior laryngeal nerve, curves around 

 the subclavian artery on the right, and the arch of the aorta on the 

 left side. It ascends in the groove between the trachea and oesopha- 

 gus, and piercing the lower fibres of the inferior constrictor muscle 

 enters the larynx close to the articulation of the inferior cornu of the 

 thyroid with the cricoid cartilage. It is distributed to all the muscles 

 of the larynx, with the exception of the crico-thyroid, and communi- 

 cates on the arytenoideus muscle with the superior laryngeal nerve. 

 As it curves around the subclavian artery and aorta it gives branches 

 to the heart and root of the lungs ; and as it ascends the neck it dis- 

 tributes filaments to the oesophagus and trachea, and communicates 

 with the external laryngeal nerve and sympathetic. 



The Anterior pulmonary branches are distributed upon the anterior 

 aspect of the root of the lungs, forming, with branches from the great 

 cardiac plexus, the anterior pulmonary plexus. 



The Posterior pulmonary branches, more numerous than the ante- 

 rior, are distributed upon the posterior aspect of the root of the lungs, 

 and are joined by branches from the great cardiac plexus, forming the 



Upon the oesophagus the two nerves divide into numerous branches 

 which communicate with each other and constitute the cesopJiageal 

 plexus which completely surrounds the cylinder of the oesophagus, and 

 accompanies it to the cardiac orifice of the stomach. 



The Gastric branches are the terminal filaments of the two pneumo- 

 gastric nerves ; they are spread out upon the anterior and posterior 

 surfaces of the stomach, and are likewise distributed to the omentum, 

 spleen, pancreas, liver, and gall-bladder, and communicate, particularly 

 the right nerve, with the solar plexus. 



SPINAL ACCESSORY NERVE. The spinal accessory nerve arises by 

 several filaments from the side of the spinal cord as low down as the 

 fourth or fifth cervical nerve, and ascends behind the ligamentum den- 

 ticulatum, and between the anterior and posterior roots of the spinal 

 nerves, to the foramen lacerum posterius. It communicates in its 

 course with the posterior root of the first cervical nerve, and entering 

 the foramen lacerum becomes applied against the posterior aspect of the 

 ganglion jugulare of the pneumogastric, being contained in the same 

 sheath of dura mater. In the jugular fossa it divides into two 

 branches ; the smaller joins the pneumogastric immediately below the 

 jugular ganglion, and contributes to the formation of the pharyngeal 

 nerve ; the larger or true continuation of the nerve passes backwards 



