This diagram of the retina, drawn by Santiago Ramon y Cajal in 1892, comes from Web Vision, a comprehensive overview of the organization of the mammalian retina and visual system compiled by Drs. Helga Kolb, Eduardo Fernandez and Ralph Nelson of the John Moran Eye Center at the University of Utah.
The site is arranged like a book and contains 14 parts. It covers the anatomy, physiology, development and regeneration of retinal circuitry; the primary visual cortex, colour vision and visual psychophysics; and the clinical electrophysiology of various retinal degenerative diseases. It also contains many illustrations, animations and Quicktime movies.