THE TENTS, VAGUS, OR PNEUMOGA8TRIC NERVE 1Q07 



Vagus. 

 Spinal accessory. 



membranous septum separating them from the glossopharyngeal, which lies in 

 iron _t_( Fig. 744). The nerve in this situation presents a well-marked ganglionic 

 enlargement, which is called the 

 superior ganglion, or jugular 

 ganglion; to it the vagal ac- 

 cessory part of the spinal ac- 

 cessory nerve is connected by 

 one or two filaments. After 

 its exit from the jugular fora- 

 men the nerve is joined by the 

 accessory portion of the spinal 

 accessory nerve and enlarges 

 into a second gangliform swell- 

 ing, called the inferior ganglion 

 or the ganglion of the trunk of 

 the nerve, through which the 

 fibres of the spinal accessory 

 nerve pass unchanged, being 

 principally distributed to the 

 pharyngeal and superior laryn- 

 geal branches of the vagus; but 

 some of the filaments from it 

 are continued into the trunk of 

 the vagus below the ganglion 

 to be distributed with the re- 

 current laryngeal nerve, and 

 probably also with the cardiac 

 nerves. The vagus nerve passes 

 vertically down the neck within 

 the sheath of the carotid ves- 

 sels lying between the internal 

 carotid artery and the internal 

 jugular vein as far as the thy- 

 roid cartilage. and then between 

 the same vein and the common 

 carotid to the root of the neck 

 (Fig. 744). From here the 

 course of the nerve differs on 

 the two sides of the body. 



On the right side (Fig. 744) 

 the nerve passes across the sub- 

 clavian artery between it and 

 the right innominate vein, and 

 descends by the side of the 

 trachea to the back part of the 

 root of the right lung, where it 

 spreads out in a plexiform net- 

 work, the posterior pulmonary 

 plexus (plexus pulmonalis pos- 

 terior], from the lower part 

 of which two cords descend upon the oesophagus, on which tube they divide, 

 forming, with branches from the opposite nerve, the oesophageal plexus (plexus 

 gulae); below, these branches are collected into a single cord, which runs along 

 the back part of the oesophagus, enters the abdomen, and is distributed to the 



FIG. 744. Course and distribution of the glossopharyngeal, vagus, 

 and spinal accessory nerves. 



