THE TENTH OR PNEUMGGASTRIC NERVE. 



Glosso-pharyngeal. 



The Tenth Pair (Figs. 403, 404). 



The Tenth or Pneumogastric Nerve (nervus vagus or par vaguni) has a more 

 extensive distribution than any of the other cranial nerves, passing through the 

 neck and thorax to the upper part 

 of the abdomen. It is composed 



, ,f, 



of both motor and sensory fibres. 



It Supplies the Organs of voice Spinal accessory. 



and respiration with motor and 

 sensory fibres, and the pharynx, 

 oesophagus, stomach, and heart 

 with motor fibres. Its superficial 

 origin is by eight or ten filaments 

 from the groove between the oli- 

 vary and the restiform body below 

 the glosso-pharyngeal ; its deep 

 origin may be traced through the 

 fasciculi of the medulla to termi- 

 nate in a nucleus of gray matter, 

 the nucleus vagi, at the lower part 

 of the floor of the fourth ventricle 

 beneath the ala cinerea below and 

 continuous with the nucleus of 

 origin of the glosso-pharyngeal. 

 -In addition to this a few fibres 

 pass into the funiculus solitarius, 

 and others into the nucleus am- 

 biguus or accessory vagal nucleus. 

 The real origin of the sensory 

 fibres of the vagus is to be found 

 in the cells of the ganglia on the 

 nerve, viz., the ganglion of the 

 root and the ganglion of the trunk. 

 The filaments become united and 

 form a flat cord, which passes out- 

 ward beneath the flocculus to the 

 jugular foramen, through which 

 it emerges from the cranium. In 

 passing through this opening the 

 pneumogastric accompanies the 

 spinal accessory, being contained 

 in the same sheath of dura mater 

 with it, a membranous septum 

 separating them from the glosso- 

 pharyngeal, which lies in front 

 (Fig. 329). The nerve in this 

 situation presents a well-marked 

 ganglionic enlargement, which is 

 called the jugular ganglion, or the 

 ganglion of the root of the pneu- 

 mogastric : to it the accessory part 

 of the spinal accessory nerve is 



connected by one or two filaments. 

 A f . .-, , f .-i f 



Alter the exit ot the nerve trom 



the jugular foramen the nerve is 



joined by the accessory portion of the spinal accessory, and enlarges into a second 



gangliform swelling, called the ganglion inferius, or the ganglion of the trunk of 



FIG. 404. Course and distribution of the ninth, tenth, and 

 eleventh nerves. 



