CEPHALIC NERVES GLOSSO -PH AR YNG E AL NERVE. 621 



to indicate that the 5th pair does not 

 Dr. J. Reid has justly observed, we 

 have no evidence that all the fila- 

 ments of the 5th pair sent to the 

 tongue were affected ; and there is 

 believed to be no case on record, in 

 which the whole of the 5th pair, or 

 of its third branch, was found to be 

 diseased after death, and in which 

 during life the sense of Taste had been 

 retained in the anterior and middle 

 parts of the tongue. Hence these 

 cases only serve to indicate what is 

 probable on other grounds ; viz., that 

 the filaments \\hich convey gustative 

 impressions are not the same with 

 those that minister to common sensa- 

 tion. On the whole, then, it seems 

 to be proved by anatomical and ex- 

 perimental evidence, that both the 

 Glosso-pharyngeal and the Fifth pair 

 minister alike to the tactile and to the 

 gustative sense ; and there is nothing 

 in the pathological facts just noticed, 

 that militates against this conclusion. 

 There seems good reason to believe 

 the Glosso-pharyngeal to be exclu- 

 sively the nerve, through which the 

 impressions made by disagreeable sub- 

 stances taken into the mouth are pro- 

 pagated to the Medulla Oblougata, so 

 as to produce nausea and to excite 

 efforts to vomit. The number of 

 fibres in this nerve is about 3500. 



494. The functions of the Pneumo- 

 gastric nerve at its roots have been 

 made the subject of particular ex- 

 amination by various experimenters ; 

 some of whom (for instance, Valentin, 

 Louget, and Morgauti) have con- 

 cluded that it there possesses no motor 

 power, but is entirely a sensory or 

 rather an afferent nerve. According 

 to these, if the roots, containing about 

 4000 smaller and 5000 larger tubules, 

 be carefully separated from those of 

 the Glosso-pharyngeal, and (which is 

 a matter of some difficulty) from 

 those of the Spinal Accessory nerve, 

 and be then irritated, no movements 

 of the organs supplied by its trunk 

 can be observed : whilst, if the roots 

 be irritated when in connection with 

 the nervous centres, muscular con- 

 tractions, evidently of a reflex char- 



minister to the sense of Taste; but, as 



FIG. 228. 



Origin and Distribution of the Eighth Pair of 

 Nerves: 1, 3, 4. The Medulla Oblongata. 1. The 

 Corpus Pyramidale of one side. 3. The Corpus 

 Olivare. 4. The Corpus Restiforme. 2. The Pons 

 Varolii. 5. The Facial Nerve. 6. The origin of 

 the Glosso-pharyngeal nerve. 7. The ganglion of 

 Andersch. 8. The trunk of the nerve. 9. The 

 Spinal Accessory nerve. 10. The ganglion of the 

 Pneuruogastric nerve. 11. Itsplexiforni ganglion. 

 12. Its trunk. 13. Its pharyngcal branch forming 

 the pharyngeal plexus (14) assisted by a brand) 

 from the glosso-pharyngeal (8) and one from the 

 superior laryngeal nerve (15). 16. Cardiac branches. 

 17. Recurrent laryngeal branch. 18. Anterior 

 pulmonary branches. 19. Posterior pulmonary 

 branches. 20. CEsophageal plexus. 21. Gastric 

 branches. 22. Origin of the Spinal Accessory 

 nerve. 23. Its branches distributed to the sterno- 

 mastoid muscle. 24. Its branches to the trapezius 

 muscle. 



