The receptor mosaic of Aotes trivirgatus: distribution of rods and cones.

The distribution and density of rods and cones have been determined in the temporal retina of the owl monkey Aotes trivirgatus. Rod density varied from 175,000/mm2 in the far periphery to 387,000/mm2 in the area centralis. Cone density was 4000/mm2 in the periphery and 7300/mm2 within the central retinal area. Variation of densities across the retina was continuous but the ratio of rods to cones remained about 50:1 at all locations. The cones are not randomly scattered, but are separated by distances of about 10 mu in central retina and 13 mu in peripheral retina.