THE GLOSSO-PHARYNGEAL NERVE. 555 



Panizza and Longet, tend to the same conclusions ; and 

 their results probably express nearly all the truth regard- 

 ing the part of the glosso-pharyngeal nerve which is 

 distributed to the pharynx. These results were that, 

 i. Pain was produced when the nerve, particularly its 

 pharyngeal branch, was irritated. 2. Irritation of the 

 nerve before the origin of its pharyngeal, or of any of 

 these branches, gave rise to extensive muscular motions of 

 the throat and lower part of the face : but when the nerve 

 was divided, these motions were excited by irritating the 

 upper or cranial portion, while irritation of the lower end, 

 or that in connection with the muscles, was followed by 

 no movement ; so that these motions must have depended 

 on a reflex influence transmitted to the muscles through 

 other nerves by the intervention of the nervous centres. 

 3. When the functions of the brain and medulla oblon- 

 gata were arrested by poisoning the animal with prussic 

 acid, irritation of the glosso-pharyngeal nerve, before it 

 was joined by any branches of the pneumogastric, gave 

 rise to no movements of the muscles of the pharynx or 

 other parts to which it was distributed ; while, on irrita- 

 ting the pharyngeal branch of the pneumogastric, or the 

 glosso-pharyngeal nerve, after it had received the commu- 

 nicating branches just alluded to, vigorous movements of 

 all the pharyngeal muscles and of the upper part of the 

 oesophagus followed. 



The most probable conclusion, therefore, may be that 

 what motor influence the glosso-pharyngeal nerve may 

 seem, to exercise, is due either to the filaments of the 

 pneumogastric or accessory that are mingled with it, or to 

 impressions conveyed through it to the medulla oblongata, 

 and thence reflected to muscles through motor nerves, 

 especially the pneumogastric, accessory, and facial. Thus, 

 the glosso-pharyngeal nerve excites, through the medium 

 of the medulla oblongata, the actions of the muscles of 

 deglutition. It is the chief centripetal nerve engaged in 



