SUPERIOR MAXILLARY NERVE. 491 



After parting with the ramifications to the nose, the remain- 

 der of the nasal branch, named external from its place of 

 distribution, continues to the internal canthus of the eye, jmd 

 sends twigs to the lachrymal sac, the caruncula lachrymalis, the 

 eyelids, and the exterior surface of the upper part of the nose. 



The Lachrymal Branch receives a filament from the fourth 

 nerve in the cavernous sinus ; it proceeds obliquely forward 

 and outwards, towards the lachrymal gland. In its course, it 

 sends off a twig, which passes through the spheno-maxillary 

 fissure, and communicates with a twig of the upper maxillary 

 nerve, and one or more twigs that pass through foramina in 

 the malar bone to anastomose over the malar bone with 

 branches of tempero-malar and facial nerves. The main 

 branch passes to the lachrymal gland, and some twigs continue 

 beyond it to the contiguous parts. 



The Superior Maxillary Nerve. 



The second branch of the fifth pair is examined with great 

 difficulty on account of its peculiar situation. It proceeds from 

 the semilunar ganglion, and passes through the foramen rotun- 

 dum of the sphenoid bone into the upper part of the zygomatic 

 fossa. In this situation it sends a twig called orbital to the 

 orbit by the spheno-maxillary fissure, and a branch, called the 

 Infra Orbitar, which appears like the main nerve as it preserves 

 a similar direction, to the infra orbitar canal. At the same place 

 it sends downwards two branches, which unite together almost 

 immediately after their origin, and, as soon as they have 

 united, enlarge into a ganglion.* The ganglion is called the 

 Spheno-palatine, or ganglion of Meckel. It is rather of a tri- 

 angular figure, and lies very near the spheno-palatine foramen. 

 It gives off a posterior branch, which passes through the ptery- 

 goid foramen to the cavity of the cranium : some branches which 

 proceed through the spheno-palatine foramen to the nose, and 

 are called the Spheno-Palatine or Lateral Nasal Nerves : and 

 an inferior branch that proceeds through the posterior palatine 

 canal, and is called the Palatine Nerve. 



The small branch, which was^rstf mentioned, as going to the 



* Sometimes a single branch passes downwards instead of two ; but it forms 

 a ganglion in the same place. 



