266 THE NERVES OP THE TEETH. 



passes beneath the ganglion of Gasser and the dura mater, 

 outwards and backwards upon the anterior cerebral sur- 

 face of the petrous bone, to the hiatus fallopii, which it 

 enters. In this canal it joins the portio dura, and accom- 

 panies this latter nerve to the posterior part of the tympa- 

 num, where it then leaves the portio dura by entering the 

 cavity of the tympanum, and here receives the name of 

 chorda tympani. Its entrance into the tympanum is below 

 the pyramid, and from this point it crosses the cavity be- 

 tween the long leg of the incus, and handle of the malleus; 

 then it emerges along with the tendon of the laxator tym- 

 pani muscle by the glenoid fissure, and now runs forwards 

 and inwards, joining in its course the gustatory nerve as 

 far as the submaxillary gland, at which point it joins the 

 submaxillary ganglion. This ganglion is found at the 

 posterior part of the submaxillary gland. 



The vidian nerve, by this lengthy and circuitous course, 

 establishes, says Mr. Harrison, several very interesting re- 

 lations : by it, the ganglion of Meckel, the superior cervi- 

 cal ganglions of the sympathetic, and the submaxillary 

 ganglion, are all connected. It also unites the superior 

 and inferior maxillary nerves, and both to the portio dura. 



The third set of branches from Meckel's ganglion pass 

 inwards, and are called the nasal or spheno-palatine. These 

 (often only a single branch) pass through the spheno- 

 palatine foramen and then separate into five or six branches, 

 which supply the mucous membrane of the upper and mid- 

 dle spongy bones. One long branch, called the nerve of 

 Cotunnius or naso-palatine, is seen to descend along the 

 septum-nasi as far as the foramen incisivum, at which 

 point it meets the anterior branches of the palatine nerves, 

 and also here a small ganglion is spoken of, but difficult 

 to be distinguished. 



An orbital branch comes off next from the superior maxil- 

 lary, this gets into the orbit through the spheno-maxillary 

 fissure, and there divides into a temporal and a molar 

 branch. The former is traced through the malar bone into 

 the temporal fossa, accompanies the temporal artery, and 



