548 THE CRANIAL NERVES. 



Twigs and Communications of the Facial Nerve in the Aqueduct of 

 Fallopius. While passing through its canal in the petrous portion of 

 the temporal bone, the facial nerve gives off a number of slender fila- 

 ments by which it communicates with other nerves or with ganglia 

 belonging to the sympathetic system. The physiological character of 

 most of these filaments is imperfectly understood ; but certain facts have 

 been established in regard to them, and they are of interest because 

 they are usually involved in injury or disease of the nerve within its 

 bony canal, and thus other secondary symptoms are produced in addi- 

 tion to those of external facial paralysis. 



Fig. 178. 



THE FACIAL NERVE AND ITS CONNECTIONS, within the aqueduct of Fallopius. 

 1. Fifth nerve, with the Gasserian ganglion. 2. Ophthalmic division of the fifth nerve. 3. 

 Superior maxillary division of the fifth nerve. 4. Lingual nerve. 5. Sphenopalatine gan- 

 glion. 6. Otic ganglion. 7. Submaxillary ganglion. 8. Facial nerve in the aqueduct of Fal- 

 lopius. 9. Great superficial petrosal nerve. 10. Small superficial petrosal nerve. 11 Stapedius 

 branch of facial nerve 12. Branch of communication with pneumogastric nerve. 13. Branch 

 of communication with glossopharyngeal nerve. 14. Chorda tympani. 



At the elbow formed ~by the anterior bend of the facial nerve, soon 

 after its entrance into the aqueduct of Fallopius, there is a minute col- 

 lection of gray matter, known as the u ganglion geniculatum." From 

 this point a slender filament, the great superficial petrosal nerve (Fig. 

 178, 9 ), runs forward, passing obliquely through the base of the skull, 

 and terminates in the sphenopalatine ganglion. This ganglion, which is 

 also in connection, by another root, with the Superior maxillary division 

 of the fifth nerve, lends filaments to the mucous membrane of the pos- 

 terior part of the nasal passages and that of the hard and soft palate 

 and to the levator palati and uvular muscles ; that is, to the dilators of 

 the isthmus of the fauces. 



This nerve, which forms communication between the facial and the 

 sphenopalatine ganglion, is without doubt the motor root of the gan- 

 glion, supplying motive force from the facial to the muscular branches 

 given off from it beyond. This conclusion is derived from the phe- 

 nomena of paralysis of the palatal muscles accompanying certain cases 



