Fig. 12. Latex injection of the blood vessels of the posterior choroid. The choroidal arteries and arterioles are the darker vessels. The biggest branch, obliquely traversing the picture, is the long posterior ciliary artery, which is actively involved in the blood supply to the choroid. The macula is located approximately in the center. The macular arteries are not of end-arterial nature, as the macula is supplied by two, nasal and temporal, choroidal arteries. The choroidal arteries and arterioles are located in the outer choroidal layer shortly after they enter the eyeball. More peripherally, they lie nearer the choriocapillaris layer. (Shimizu K, Ujiie K: In Delaey JJ, ed: Fluorescein angiography and angioarchitecture of the choroid. International Symposium on Fluorescein Angiography. Doc Ophthalmol 9:187, 1976)