NERVOUS SYSTEM. 337 



texture as, those little knots or swellings in other parts whicii 

 we are in the habit of calling ganglia. Waving this remark, 

 however, and calling it a ganglion, we say that three nerves 

 depart from it; and to these we give names from the parts 

 they are destined principally to supply, viz. the ophthalmic, the 

 superior maxillary y and the inferior maxillari/ nerve. 



The OPHTHALMIC NERVE, the Smallest of the three divisions, 

 proceeds for a short way down the sinus in union with the supe- 

 rior maxillary ; inclining forward, however, it soon leaves that 

 nerve, and takes its passage through the foramen lacerum orbi- 

 tale into the orbit. As it emerges from this opening it splits 

 into three branches — the lachrymal, the supra-or hilar, and the 

 lateral nasal branch. 



The lachrymal branch, at its origin, comprehends two divi- 

 sions. One is a long single nerve that ascends behind the 

 muscles of the eye, through the fatty matter at the bottom of 

 the orbit, winds over the angle formed between the zygoma and 

 the frontal orbital process, and ends in subcutaneous and anas- 

 tomosing branches about the forehead. The other consists of 

 several filaments which run forward over the fatty matter enve- 

 loping the eye, and are distributed to the lachrymal gland, con- 

 junctiva, and ciliary glands of the upper eyelid. 



The supra-orbitar branch takes the same superficial course 

 across the roof of the orbit to the inner angle of the orbitar ridge, 

 where it passes through the foramen supra-orbitarium, and after- 

 wards ramifies upon the skin covering the forehead. It gives off 

 a twig or two to the adipose matter of the eye, and sends a 

 branch to the upper lid. 



The lateral nasal branch, the largest of the three, makes a 

 sudden turn inward, and runs between the levator and retractor 

 oculi ; and, after having detached a considerable branch to the 

 membrana nictitans, enters again the cavity of the cranium, 

 through the foramen orbitale internum, from which it takes its 

 passage, through one of the holes in the cribriform plate, into 

 the chamber of the nose. Herein it creeps along the top of the 

 anterior turbinated bone, within a bony and membranous canal, 

 immediately covered by the more prominent part of the os nasi ; 

 and sends its ultimate branches to the false nostril and wing of 

 the nose. Near its origin, this nerve sends a twig or two to 

 the ophthalmic ganglion. 



The second division, or superior maxillary nerve, much 

 larger than the ophthalmic, leaves the cranium through the 

 foramen rotundum of the sphenoid bone, and takes its pas- 

 sage along the canalis infra-orbitarius, whence it emerges, 

 covered by the levator labii superioris, upon the face : here it 



