THE OR AXIAL NERVES. 139 



nerve will excite a copious flow. This is an active secretion, and is 

 not a simple filtration due to vaso-motor changes. A similar influ- 

 ence is noted in the corresponding half of the tongue. There is a 

 similar distribution of fibres from the facial to the parotid gland 



FIG. 40. 



Facial Paralysis of the Right Side. 



through the lesser petrosal nerve, but their action has not been so 

 thoroughly analyzed as in the case of the submaxillary and chorda 

 tympani. 



The chorda tympani has still further an effect upon the sense of 

 taste in the anterior portion of the tongue. If it be divided, the 

 taste is much blunted on the affected side. It is not known if this 

 be due to the communication of the glosso-pharyngeal or not, but 

 it seems probable that it cannot be ascribed to either the trifacial 

 or facial alone ; and it is considered to be a plausible explanation 

 that the chorda tympani does bear some fibres of the glosso- 

 pharyngeal. 



