610 THE CRANIAL NERVES. 



of the submaxillary gland. Others from the fore part of the ganglion, 

 longer and larger than the preceding, end in the mucous membrane of the 

 mouth, and iu Whartou's duct. 



According to Meckel (" De quinto pare," &c ), a branch occasionally descends in 

 front of the hyo-glossus muscle, and after joining with one from the hypoglossal nerve, 

 ends in the genio-hyo-glossus muscle. 



It may be noticed that while the branches from the otic ganglion 

 pass exclusively to muscles, the submaxillary ganglion gives no muscular 

 offsets. 



Summary. Cutaneous filaments of the inferior maxillary nerve ramify on 

 the side of the head, and the external ear, in the auditory passage, the 

 lower lip, and the lower part of the face ; sensory branches are supplied 

 by it to the greater part of the tongue ; and branches are furnished to the 

 mucous membrane of the mouth, the lower teeth and gams, the salivary 

 glands, and the articulation of the lower jaw. 



This nerve supplies the muscles of mastication, viz., the masseter, tem- 

 poral, and two pterygoid ; also the buccinator, the mylo-hyoid, and the 

 anterior belly of the digastric ; and from the otic ganglion proceed the 

 branches to the circumflexus ]_ alati and tensor timpani muscles. 



SIXTH PAIR OF NERVES. 



The sixth cranial nerve (nerv. abducens) enters the dura mater behind 

 the dorsum sellae, and passing forwards in the floor of the cavernous sinus, 

 close to the outer side of the carotid artery, enters the orbit through the 

 sphenoid al fissure, and between the heads of the external rectus muscle, 

 and is entirely distributed to that muscle, piercing it on the ocular surface. 

 In entering the orbit between the heads of the external rectus muscle, it is 

 beneath the other nerves, but above the ophthalmic vein. While passiiig 

 along the internal carotid artery in the cavernous sinus, it is joined by several 

 filaments of the sympathetic from the carotid plexus. According to 

 Bock, it is joined iu the orbit by a filament from Meckel's ganglion. 

 (" Beschreibuug des Funfteu Nervenpaares." 1817.) 



SEVENTH PAIR OF NERVES. 



In the seventh cranial nerve of Willis are comprised two nerves having 

 a distinct origin, distribution, and function. One of these, the facial, is the 

 motor nerve of the face ; the other, the auditory, is the special nerve of the 

 organ of hearing. Both enter the internal auditory meutus in the tem- 

 poral bone, but they are soon separated from each other. 



FACIAL NERVE. 



The facial nerve, or portio dura of the seventh pair, is inclined outwards 

 with the auditory nerve, from its place of origin, to the internal auditory 

 meatus. The facial lies in a groove on the auditory nerve, and the tAvo are 

 united in the auditory meatus by one or two small filaments. At the bot- 

 tom of the meatus the facial nerve enters the aqueduct of Fallopius, and 

 follows the windings of that canal to the lower surface of the skull. The 

 nerve passes through the temporal bone at first almost horizontally outwards, 

 between the cochlea and vestibule ; on reaching the inner wall of the tyrn- 



