VISION. 777 



vals between the vessels are elongated, stellate pigment-cells. The 

 inner part of the choroid is formed mainly by capillary blood-vessels 

 (tunica Euyschiana vel chorio-capillaris). This reaches to one- 

 eighth of an inch from the corneal margin, where its vessels join 

 those of the ciliary processes. On the inner surface of the tunica 

 Euyschiana is a structureless membrane, the membrane of Bruch, 

 which lies next to the pigmentary layer of the retina. The choroid 



Fig. 327. Meridional Section of the Human Ciliary Body. 

 (BoHM and DAVIDOFF.J 



1, 2, Conjunctiva. 3, Sclera. 4, Meridional fibers of the ciliary muscle. 

 5, Ciliary processes. 6, Circular fibers of the ciliary muscle. 1, Iris pigment. 

 8, Stroma of iris. 9, Canal of Schlemm. 10, Membrane of Descemet. 11, Cor- 

 nea. 12, Corneal epithelium. 



coat ends anteriorly in the ciliary processes and the iris. The 

 ciliary processes consist of about seventy to eighty ridgelike pro- 

 cesses running meridionally. They are arranged around the lens, 

 and toward the outside the ground-substance of the processes bor- 

 ders on the ciliary muscle. They have the same structure as the 

 choroid, and contain very numerous blood-vessels, derived from the 

 anterior ciliary arteries. 



