INFERIOR MAXILLARY NERVE. 605 



The large superficial petrosal branch of the Vidian nerve, entering the cranium on 

 the outer side of the carotid artery and beneath the Gasserian ganglion, is directed 

 backwards in a groove on the petrous portion of the temporal bone to the hiatus 

 Fallopii, and is thus conducted to the aqueductus Fallopii, where it joins the gangli- 

 form enlargement of the facial nerve. 



The carotid or sympathetic portion of the Vidian nerve, shorter than the other, is 

 of a reddish colour and softer texture : it is directed backwards, and on the outer 

 side of the carotid artery ends in the filaments of the sympathetic surrounding that 

 vessel. 



In accordance with the view taken of the ganglia connected with the fifth nerve 

 (p. 599), the superficial petrosal and carotid parts of the Vidian nerve may be regarded 

 as the motor and sympathetic roots respectively of the spheno-palatine ganglion; the 

 spheno-palatiue being its sensory root. 



The pharyngeal nerve is inconsiderable in size, and, instead of emanating directly 

 from the ganglion, is frequently derived altogether from the Vidian. This branch, when 

 a separate nerve, springs from the back of the ganglion, enters the ptery go-palatine 

 canal with an artery, and is lost in the lining membrane of the pharynx behind the 

 Eustachian tube. 



Summary. The superior maxillary nerve, with Meckel's ganglion, supplies 

 the integument above the zygomatic arch, and that of the lower eyelid, the 

 side of the nose, and the upper lip ; the upper teeth, the lining mem- 

 brane of the nose ; the membrane of the upper part of the pharynx, of the 

 antrum of Highmore, and of the posterior ethmoid cells ; the soft palate, 

 tonsil, and uvula ; and the glandular and mucous structures of the roof of 

 the mouth. 



INFERIOR MAXILLARY NERVE. 



The lower maxillary nerve, the third and largest division of the fifth 

 nerve, is made up of two portions, unequal in size, the larger being derived 

 from the Gasserian ganglion, aud the smaller being the slender motor root 

 of the fifth nerve. These two parts leave the skull by the foramen ovale 

 in the sphenoid bone, and unite immediately after their exit. A few lines 

 beneath the base of the skull, and under cover of the external pterygoid 

 muscle, the nerve separates into two primary divisions, one of which is 

 higher in position and smaller than the other. 



The small, anterior or upper portion, purely motor, terminates in 

 branches to the temporal, masseter, buccinator, and pterygoid muscles. The 

 larger or lower portion, chiefly sensory, divides into the auriculo-temporal, 

 gustatory, and inferior dental branches : it likewise supplies the mylohyoid 

 muscle, and the anterior belly of the digastric. The branch to the in- 

 ternal pterygoid muscle, with which also are connected those proceeding 

 from the otic ganglion to the tensors of the palate and tympanum, is 

 sometimes counted as a part of the larger division, but is more correctly 

 regarded as arising from the undivided trunk. 



DEEP TEMPORAL, MASSETERIC, BUCCAL, AND PTERYGOID BRANCHES. 



The deep temporal branches, two in number, anterior and posteriory pass 

 outwards above the external pterygoid muscle, close to the bone, and run 

 upwards, one near the front, and the other near the back of the tem- 

 poral fossa, beneath the temporal muscle in the substance of which they 

 are distributed. (See fig. 403.) 



The anterior branch is frequently joined with the buccal nerve, and 

 sometimes with the other deep temporal branch. 



The masseteric branch likewise passes above the external pterygoid 



