THE TENTH OR PNEUMGGASTRIC NERVE. 



749 



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 



, , . , ff, 



of both motor and sensory fibres. 



It supplies the organs of voice 



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 mattei', 



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. 



After the exit of the nerve irom 



the jugular foramen the nerve is 



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



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



\ 





^ ^ _ courge and distribution of 

 eleventh nerves. 



ninth> tenth, and 



