Fig. 7 Simplified circuitry of primate retina. The major retinal cell types and their connections are shown. Cones are designated as S, M, or L. Diffuse bipolars and midget bipolars are each present as ON and OFF types. A special S cone bipolar cell is shown. Ganglion cells are of the parasol (MC), midget (PC), or small bistratified (S cones, KC) types. (Reprinted from Lee BB: Receptors, channels and color in primate retina. In Backhaus WGK, Kliegl R, Werner JS (eds): Color Vision: perspectives from different disciplines. Berlin: Walter de Gruyter, 1998:79–88. Copyright 1998. Reproduced with permission of Walter de Gruyter Gmbtl Co. KG.)