FACIAL. 541 



hiatus Fallopii, where it forms a reddish gangliforra swelling (intumescentia 

 gangliformis), and is joined by several nerves ; bending suddenly backwards, it 

 runs in the internal wall of the tympanum, above the fenestra ovalis, and 

 at the back of this cavity passes vertically downwards to the stylo-mastoid 

 foramen. 



On emerging from this aperture, it runs forwards in the substance of the parotid 

 gland, crosses the external carotid artery, and divides behind the rarnus of the 

 lower jaw into two primary branches, temporo-facial and cervico-facial, from 

 which numerous offsets are distributed over the side of the head, face, and upper 

 part of the neck, supplying the superficial muscles in these regions. 



The communications of the facial nerve may be thus arranged : 



In the internal auditory rneatus . AVith the auditory nerve. 



f With Meckel's ganglion by the large 

 petrosal nerve. 



i -n 11 With the otic ganglion by the small 



In the aquaeductus Fallopii . < * 



petrosal nerve. 



With the sympathetic on the middle me- 

 ningeal by the external petrosal nerve. 

 f With the pneumogastric. 

 At its exit from the stylo-mastoid glossary ngeal. 



foramen carotl( * . 



auricularis magnus. 



" auriculo-temporal. 

 On the face . . . . With the three divisions of the fifth. 



In the internal auditory meatus, some minute filaments pass between the facial 

 and auditory nerves. 



Opposite the hiatus Fallopii, the gangliform enlargement on the facial nerve 

 communicates, by means of the large petrosal nerve, with Meckel's ganglion, 

 forming its motor root ; by a filament from the small petrosal with the otic 

 ganglion ; and by the external petrosal, with the sympathetic filaments accom- 

 panying the middle meningeal artery (Bidder). From the gangliform enlarge- 

 ment, according to Arnold, a twig is sent back to the auditory nerve. 



At its exit from the stylo-mastoid foramen, it sends a twig to the pneumogastric, 

 another to the glosso-pharyngeal nerve, and communicates with the carotid plexus 

 of the sympathetic, with the great auricular branch of the cervical plexus, with 

 the auriculo-temporal branch of the inferior maxillary nerve in the parotid gland, 

 and on the face with the terminal branches of the three divisions of the fifth. 



BRANCHES OF DISTRIBUTION'. 



Within aqujeductus Fallopii ^g*' 



( Chorda tympam. 



At exit from stylo-mastoid ( P? 8 *' auricular. 

 foramen . . j ^'gastric. , 



( Stylo-hyoid. 



( Temporal. 



f Temporo-facial 4 Malar. 



On the face Infra-orbital. 



I Buccal. 



[ Cervico-facial < Supra-maxillary. 

 ( Infra-maxillary. 



The Tympanic branch arises from the nerve opposite the pyramid; it is a small 

 filament, which supplies the Stapedius and Laxator tympani muscles. 



