3 28 ANTHROPOLOGY. 



'). The Trigemini : Trifacial. Fiftit Pair. This emerges by three 

 I'oots from the side of the pons Varohi, just where it is continuous with the 

 crus cerebelli, and after forming the semilunar or Gasserian ganglion^ is 

 «livided into three hirge branches, the ophthalmic, the superior, and the 

 inferior maxillary. 



The ophthalmic passes along the outer side of the cavernous sinus, and 

 approaching the foramen lacerum orbitale, divides into three branches, the 

 lachrymal, the frontal, and the nasal. The lachrymal is ultimately distri- 

 buted to the conjunctiva and lachrymal gland. The frontal divides into an 

 i)iternal or supra-trochleator nerve, to the region of the eye, and the external, 

 supra-orhital, or proper frontal nerve^ to the scalp. Both the frontal and 

 lachrymal are nerves of sensation. The nasal nerve divides into two 

 branches, the external or infra-trochleator to the lachrymal passages and the 

 i-egion of the nose, and the internal or piroper nasal. 



The superior mamillary nerve is larger than the ophthalmic, and passes from 

 1 he middle of the ganglion forwards through the foramen rotundum into the 

 J itery go-maxillary fossa. Here it sends down two small branches, which 

 ultimately unite in the splieno-palatine ganglion or the ganglion of Meckel. 

 From this proceed three sets of branches, an inferior, internal, and posterior. 

 The inferior or palatine nerves are distributed to the palate and uvula. The 

 internal branch, or the spheno-palatine nerve, divides into several branches 

 after passing into the upper and back part of the nose ; the principal of 

 these is the naso-p)alatine nerve or nerve of Cotunnius. The third or posterior 

 branch of the ganglion is the vidian or superior petrosal nerve, distributed to 

 the tympanic apparatus. 



Other branches' sent off by the superior maxillary are, the orbital, the 

 malar, the temporal, the i)osterior dental, the infra-orbital, and the anterior 

 dental^ all of which indicate their distribution in their names. 



The inferior maxillary nerve descends from the ganglion through the 

 ibramen ovale into the zygomatic fossa, where it divides into two large 

 branches, a superior or external, and an inferior or internal. The former sub- 

 divides into the two deej) temporal, the masseteric, the buccal and the ptery- 

 goid ; the latter into the auricular, inferior dental, and gustatory nerves ; most 

 of these have various subdivisions. 



6. Motor Externus Oculi. Sixth Pair. This ariges from the base or 

 upper portion of the corpus pyramidale, under the posterior margin of the 

 tuber annulare, or pons ; the fibres are assembled into two roots, of which 

 the external is much the larger. These roots, uniting, pass through the 

 sphenoidal foramen, and are distributed to the abductor oculi muscles. 



7 a. Facial Nerve or Portio Dura of the Seventh Pair. This arises 

 by two branches ; the larger from the medulla oblongata, at the most supe- 

 rior part of the corpus restiforme; the smaller from that portion of the 

 medulla oblongata placed between the first branch and the auditory nerve. 

 The two branches are kept disjtinct for the distance of several lines, when 

 they unite, and, passing into the meatus auditorius internus and through the 

 aqueduct of Fallopius, emerge at the stylo-mastoid foramen, to be distributed 

 upon the muscles and skin of the head. In the aqueduct of Fallopius it 

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