1096 



THE ORGANS OF SPECIAL SENSE 



The Ciliary Body (corpus ciliare) (Fig. 805) joins the choroid to the margin 

 of the iris. It is in reality a process of the choroid and comprises the orbiculus 

 ciliaris, the ciliary processes, and the Ciliary muscle. 



The orbiculus ciliaris (annulus ciliaris) (Figs. 803 and 804) is a zone of about 

 4 mm. (one-sixth of an inch) in width, directly continuous with the anterior part 

 of the choroid; it presents numerous ridges arranged in a radial manner. The 

 depressions between the ridges are filled with retinal pigment epithelium (Szymo- 

 nowicz). The orbiculus contains no lamina choriocapillaris. 



VENA 

 VORTICOSA 



I ANTERIOR 



CILIARY 

 <. ARTERY 



SHORT 



POSTERIOR 



CILIARY 



ARTERIES 



LONG POSTERIOR 

 CILIARY ARTERY 



FIG. 801. Vessels and nerves of the choroid and iris, seen from above, 

 been largely removed. (Testut.) 



The sclera and cornea have 



The ciliary processes (processus ciliares) (Figs. 805 and 820) are formed by the 

 plaiting and folding inward of the various layers of the choroid (i. e., the choroid 

 proper and the lamina basalis) at its anterior margin, and are received between 

 corresponding foldings of the suspensory ligament of the lens, thus establishing 

 a connection between the choroid and inner tunic of the eye. They are arranged 

 in a circle, and form a sort of plaited frill, the corona ciliaris, behind the iris, round 

 the margin of the lens (Figs. 805 and 820). They vary between sixty and eighty^ 

 in number, lie side by side, and may be divided into large and small; the latter, 

 consisting of about one-third of the entire number, are situated in the spaces 

 between the former, but without regular alternation. The larger processes are 

 each about 2.5 mm. (one-tenth of an inch) in length, and are attached by their 

 periphery to three or four of the ridges of the orbiculus ciliaris, and are continuous 

 with the layers of the choroid; the opposite margin is free, and rests upon the 

 circumference of the lens. Their anterior surface is turned tow r ard the back of 

 the iris, with the circumference of which they are continuous. The posterior 

 surface is connected with the suspensory ligament of the lens. 



