CHAPTEE XVIII 



THE EYE 



GENERAL CONSIDERATIONS 



The eye may be said to consist of the visual organ, or globe, and its 

 appendages the eyelids, conjunctiva, and lacrimal apparatus whose 

 function is chiefly protective. 



The globe of the eye, or eye proper, is contained within the cavity 



FIG. 536. DISSECTION OF EYELIDS AND LACRIMAL APPARATUS. 



1, upper lacrimal gland; 2, lower lacrimal gland and excretory ducts; 3, mouths 

 of excretory ducts: 4, tarsal (Meibomian) glands; 5, puncta lacrimalia; 6, lacri- 

 mal canaliculi; 7, lacrimal sac and nasal duct; 8, caruncula. (After Fox.) 



of the orbit, its posterior two-thirds being embedded in a mass of intra- 

 orbital fat whose inner surface is covered by a thin fibrous membrane or 

 fascia which is clothed with mesenchymal epithelium. The epithelium 

 is reflected from this fascia to the surface of the ocular globe, along a 

 line just posterior to the border of the conjunctiva, whence it passes 

 over the surface of the globe as far posteriorly as the optic nerve, on 



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