VISUAL ORGAX. 363 



:t small plate of cartilage. The small glands which usually 

 are found here probably represent the glands of Harder of 

 lower mammals. 



The car u uvula lachry mails is covered with stratified pave- 

 ment epithelium, and may contain small hairs, sebaceous 

 glands, coil glands (accessory tear glands), etc. 



Into each eyelid there enter two palpebral arteries, one from 

 the outer and the other from the inner angle of the eye (lateral 

 and medial arteries). The two arteries join together on the 

 anterior surface of the tarsus in the neighborhood of the lid 

 border. This gives rise to the arcus tarseus. At the upper 

 edge of the tarsus the arterial branches may form a second 

 arch, which is often the case in the upper lid. Both arches 

 break up into numerous branches which supply the skin, the 

 muscle, the glands, and the whole conjunctiva. The vessels 

 of the bulbar conjunctiva join at the border of the cornea 

 with the arterise ciliares anticse by numerous anastomoses. 



The lymph-vessels form two plexuses which anastomose 

 with one another. One lies in front of, the other behind, the 

 tarsus. The bulbar conjunctiva contains in the tunica propria 

 a capillary plexus of lymph-vessels which, according to Teich- 

 niann, Toldt, and others, is entirely closed at the border of the 

 cornea. According to others (Waldeyer), it is in communica- 

 tion with the lymph system of the cornea. 



The nerves form dense plexuses in the tarsus and also in the 

 conjunctiva. The fibres derived from these supply the skin, 

 muscle, vessels, and Meibomian glands. The latter become 

 surrounded by fine networks of fibres. In the conjunctiva 

 some of the fibres end in blood-vessels, others by free intra- 

 epithelial arborizations ; while the great majority terminate in 

 round or oval end bulbs, which lie in the papillae of the border 

 of the lid and the neighboring conjunctiva, and in the tunica 

 propria immediately under the epithelium in other parts of the 

 conjunctiva. 



