CEREBROSPINAL NERVES 393 



To commence with, it possesses (1) a sensory and (2) a motor root. 

 The sensory root springs from the anterior part of the pons varolii, 

 and has upon it a large elongated body, the Gasserian ganglion. From 

 this spring three branches, termed respectively the ophthalmic, superior 

 maxillary, and inferior maxillary nerves. 



The motor root is the smaller of the two, and is situated on the 

 inner side of the longer one, with which it takes origin from the pons 

 varolii. From this point it proceeds forward to unite with the inferior 

 maxillary nerve, which is now both sensitive and motor. 



The superior maxillary division is the largest of the several branches 

 of this nerve; it leaves the cranium through the foramen rotundum. The 

 ophthalmic, which is the smallest, passes out by the foramen lacerum 

 orbitale, and the inferior maxillary division by the anterior opening in 

 the foramen lacerum biisis cranii. 



On emerging from these openings the ophthalmic branch gives off — 



1. The Frontal or Supra-Orbital after emerging from the supra-orbital 

 foramen is distributed to the skin of the forehead and the upper eyelid. 



2. The Lachrymal Nerve to the lachrymal gland and the muscles and 

 skin of the ear. 



3. The Palpebro-Nasal Nerve to the inner angle of the eye, the 

 lachrymal apparatus, and the lower eyelid. It also supplies the membrana 

 nictitans, and sends a branch to the sensitive roots of the ophthalmic 

 ganglion. 



The Superior Maxillary Nerve emerges from the cranium at the 

 foramen rotundum and enters the superior dental canal. It gives off, 

 among others — 



1. The Orbital branch to the eyelids and skin. 



2. Great Anterior or Palatine Nerve traverses the palatine canal and 

 is distributed to the hard palate and gums. 



3. The Stapliyline or Posterior Palatine Nerve to the velum palati and 

 soft palate. 



4. Nasal or Spheno-Palatine Nerve to the mucous membrane of the 

 nose. 



5. The Dental Nerve to the superior molar, incisor, and canine 

 teeth. 



6. The Infra-Orbital Nerve to the nostrils and upper lip, after uniting 

 with a branch of the fixcial nerve. 



The Inferior Maxillary Nerve, as we have already pointed out, 

 contains both sensory and motor filaments. It gives off — 



1. The Masseteric Nerve, to the masseter and temporal muscles. 



2. The Buccal Nerve, to the external pterygoid mu.scle, to the orbital 



