OPHTHALMIC. 



4G5 



the lachrymal gland. Its terminal branches, escaping from the gland, are dis- 

 tributed to the upper eyelid and conjunctiva, anastomosing with the palpebral 

 arteries. The lachrymal artery gives off one or two malar branches ; one of 

 which passes through a foramen in the malar bone to reach the temporal fossa, 



Fig. 280. The Ophthalmic Artery and its Branches, the Tfroof of the Orbit having been removed. 



Anitriar JESiFua'Jn 7. 



and anastomoses with the deep temporal arteries. The other appears on the 

 cheek, and anastomoses with the transverse facial. A branch is also sent back- 

 wards, through the sphenoidal fissure, to the dura mater, which anastomoses 

 with a branch of the middle meningeal artery. 



Peculiarities. The lachrymal artery is sometimes derived from one of the anterior branches 

 of the middle meningeal artery. 



The supraorbital artery, the largest branch of the ophthalmic, arises from that 

 vessel above the optic nerve. Ascending so as to rise above all the muscles 

 of the orbit, it passes forwards, with the frontal nerve, between the periosteum 

 and Levator Palpebraa ; and passing through the supraorbital foramen, divides 

 into a superficial and deep branch, which supply the muscles and integument 

 of the forehead and pericranium, anastomosing with the temporal, angular 

 branch of the facial, and the artery of the opposite side. This artery in the 

 orbit supplies the Superior Rectus and the Levator Palpebras, sends a branch 

 inwards, across the pulley of the Superior Oblique muscle, to supply 'the parts 

 at the inner canthus ; and at the supraorbital foramen, frequently transmits a 

 branch to the diploe. 



The ethmoidal branches are two in number; posterior and anterior. The 

 former, which is the smaller, passes through the posterior ethmoidal foramen, 

 supplies the posterior ethmoidal cells, and entering the cranium, gives off a 

 meningeal branch, which supplies the adjacent dura mater, and nasal branches, 

 which descend into the nose through apertures in the cribriform plate, anasto- 

 mosing with branches of the spheno-palatine. The anterior ethmoidal artery 

 accompanies the nasal nerve through the anterior ethmoidal foramen, supplies 

 30 



