This project involves the study of the anatomical properties and organization of cells in the visual system of primates, with emphasis on the retina and the visual cortex. The blue-sensitive cones of the macaque retina were selectively labelled using tissue-reactive dyes injected into the vitreous humour, and the spatial properties of the retinal point pattern of these cones was examined. We have developed a model describing the degree of regularity and structure of the cone pattern. To evaluate the topographical relationship between the cones and ganglion cells of the area centralis of human and macaque retina, especially in the fovea, we have also studied and quantified the radial displacement between photoreceptors and postreceptoral cells, and measured the density of both cones and ganglion cells. Correction for such displacement permits the topographical comparison of the densities of these two cell types in terms of visual angle; this comparison allows for an estimate of the overall degree of convergence of cones to ganglion cells, and provides boundaries for the areal coverage factor of these cells. We have also compared the density of ganglion cells to that of cells of the lateral geniculate nucleus (LGN), both for the parvocellular and the magnocellular streams; this comparison provides information about central magnification properties in this nucleus.