380 NERVOUS SYSTEM. 



This nerve is impressed on its internal face by a longitudinal 

 furrow for the reception of the facial nerve. It passes oblique- 

 ly forwards and outwards beneath the crus cerebelli, and pene- 

 trates into the meatus auditorius internus. It adheres some- 

 what near its root to the under anterior margin of the cere- 

 bellum, just behind the crus of the latter: the circumstance is 

 considered by J. F. Meckel, as a proof of its having there ano- 

 ther origin, whereby an analogy is established between it and 

 the two other nerves of tfre senses; to wit, the optic and the 

 olfactory. 



The distribution of this nerve is confined to the labyrinth of 

 the ear. 



The Eighth Pair of Nerves is composed of the Glosso-Pharyn- 

 geal, the Pneumogastric and the Spinal Accessory.* 



The Glosso-Pharyngeal Nerve (Nervus Glosso-Pharyngeus, of 

 Eighth Pair,) arises from the posterior cord of the medulla ob- 

 longata, just above, and somewhat anterior to the superior fila- 

 ments of the next nerve, with which it is very closely connected. 

 Its filaments, which are five or six in number, spring, therefore, 

 from the anterior margin of the corpus restiforme, or from the 

 fissure separating it from the corpus olivare,t under the posterior 

 margin of the tuber annulare. 



Its filaments soon collect into a round cord, and anastamose ? 

 even in the cavity of the cranium, by a considerable branch 

 with the pneumogastric. It runs outwards and backwards to 

 the foramen lacerum posterius, and goes through the same divi- 

 sion of it that the pneumogastric does, but in its own canal of 

 the dura mater. About half an inch from this canal it enlarges 

 within the cranium, into a small oblong ganglion of five or six 

 lines long, which extends itself as far as the foramen Iacerum4 



Its general distribution is to the tongue and to the pharynx, 

 as its name implies. 



* For an interesting course of experiments on the eighth pair, by John Reid, M, 

 D., see Essays on Physiology, Phila., 1838, from the Edinburgh Med. and Surgi- 

 cal Journal. 



t The Corpus Olivare is considered by Mr. Solly as its origin. 



t This ganglion is described by Andersech and by Huber, but its existence is- 

 questioned by Bichat. 



