





trachea, and from its recurrent nerve; on the left side from the recurrent nerve only; 

 passing inward, they end in the deep part of the cardiac plexus. 



The Anterior Bronchial Branches (rami bronchioles anter lores; anterior or 'central 

 pulmonary branches}, two or three in number, and of small size, are distributed 

 on the anterior surface of the root of the lung. They join with filaments from the 

 sympathetic, and form the anterior pulmonary plexus. 



The Posterior Bronchial Branches (rami bronchioles posteriores; posterior or dorsal 

 pulmonary branches), more numerous and larger than the anterior, are distributed 

 on the posterior surface of the root of the lung; they are joined by filaments from 

 the third and fourth (sometimes also from the first and second) thoracic ganglia 

 of the sympathetic trunk, and form the posterior pulmonary plexus. Branches from 

 this plexus accompany the ramifications of the bronchi through the substance of 

 the lung. 



The Esophageal Branches (rami oesophagei) are given off both above and below 

 the bronchial branches; the lower are numerous and larger than the upper. They 

 form, together with the branches from the opposite nerve, the esophageal plexus. 

 From this plexus filaments are distributed to the back of the pericardium. 



The Gastric Branches (rami gastrici) are distributed to the stomach. The right 

 vagus forms the posterior gastric plexus on the postero-inferior surface of the stomach 

 and the left the anterior gastric plexus on the antero-superior surface. 



The Celiac Branches (rami coeliaci) are mainly derived from the right vagus: they 

 join the celiac plexus and through it supply branches to the pancreas, spleen, 

 kidneys, suprarenal bodies, and intestine. 



The Hepatic Branches (ram i hepatici) arise from the left vagus : they join the hepatic 

 plexus and through it are conveyed to the liver. 



THE ACCESSORY NERVE (N. ACCESSORIUS; ELEVENTH NERVE; 

 SPINAL ACCESSORY NERVE) (Figs. 792, 793, 794). 



The accessory nerve consists of two parts: a cranial and a spinal. 



The Cranial Part (ramus internus; accessory portion) is the smaller of the two. 

 Its fibers arise from the cells of the nucleus ambiguus and emerge as four or five 

 delicate rootlets from the side of the medulla oblongata, below the roots of the 

 vagus. It runs lateralward to the jugular foramen, where it interchanges fibers 

 with the spinal portion or becomes united to it for a short distance; here it is also 

 connected by one or two filaments with the jugular ganglion of the vagus. It 

 then passes through the jugular foramen, separates from the spinal portion and 

 is continued over the surface of the ganglion nodosum of the vagus, to the surface of 

 which it is adherent, and is distributed" principally to the pharyngeal and superior 

 laryngeal branches of the vagus. Through the pharyngeal branch it probably sup- 

 plies the Musculus uvulae and Levator veli palatini. Some few filaments from it 

 are continued into the trunk of the vagus below the ganglion, to be distributed with 

 the recurrent nerve and probably also with the cardiac nerves. 



The Spinal Part (ramus externus; spinal portion) is firm in texture, and its fibers 

 arise from the motor cells in the lateral part of the anterior column of the gray sub- 

 stance of the medulla spinalis as low as the fifth cervical nerve. Passing through the 

 lateral funiculus of the medulla spinalis, they emerge on its surface and unite to 

 form a single trunk, which ascends between the ligamentum denticulatum and the 

 posterior roots of the spinal nerves, enters the skull through the foramen magnum, 

 and is then directed to the jugular foramen, through which it passes, lying in the 

 same sheath of dura mater as the vagus, but separated from it by a fold of the 

 arachnoid. In the jugular foramen, it receives one or two filaments from the 

 cranial part of the nerve, or else joins it for a short distance and then separates from 

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