356 HUMAN ANATOMY. 



The other arteries supplying the eye and its appendages are 

 derived from the ophthalmic branch of the internal carotid (the 

 same source as the ciliary arteries), the anterior cerebral branch 

 "of the internal carotid, and the infraorbital branch of the in- 

 ternal maxillary. 



The branches of the ophthalmic are the 



Lachrymal ; 



Supraorbital ; 



Anterior and posterior ethmoidal; 



Palpebral; 



Frontal ; 



Nasal. (For description see Arterial System.) 



The veins of the eyeball emerge as the vence vorticosce, unite 

 with the other veins to form two main trunks the ophthalmic 

 and inferior ophthalmic veins to terminate in the cavernous 

 sinus. The ophthalmic vein anastomoses freely with the angular 

 vein, the commencement of the facial at the inner angle of the 

 orbit. 



The nerves of the eye and its appendages are nerve of special 

 sense, the optic or second cranial; motor nerves, the third and 

 fourth; branches of the fifth and sixth, and filaments from the 

 sympathetic. 



Sensory nerve /ophthalmic division of the trifacial, or fifth 

 cranial (vide Cranial Nerves). 



Sympathetic branches, derived chiefly from the ciliary gan- 

 glion, Meckel's ganglion, and the cavernous and carotid plexuses 

 (vide Cranial Sympathetic Ganglion). 



APPENDAGES OF THE EYE. 



The appendages of the eye, or the tutamina oculi, include : 



The eyebrows (supcrcilia), Lachrymal gland, 



The eyelids (palpebrwj, Lachrymal sac, 



Conjunctiva, Nasal duct. 



THE EYEBROWS are the elevated arches of skin surmounting 

 the upper margins of the orbits, covered with short, thick hairs. 



THE EYELIDS are two movable folds, covering and protecting 

 the front of the eye. The upper lid is larger, longer, and most 

 movable, being supplied with a special muscle the levator labii 

 superioris. 



The lids are separated by an elliptical fissure the fissura 

 palpebrarum and connected at their angles of junction by the 

 outer and inner canthi. 



