Packing arrangement of the three cone classes in primate retina.

We describe a detailed analysis of the spatial arrangement of L, M and S cones in the living eyes of two humans and one monkey. We analyze the cone mosaics near 1 degrees eccentricity using statistical methods that characterize the arrangement of each type of cone in the mosaic of photoreceptors. In all eyes, the M and L cones are arranged randomly. This gives rise to patches containing cones of a single type. In human, but not in monkey, the arrangement of S-cones cannot be distinguished from random.