Retinal illumination was measured in 3 excised human eyes and 14 excised rabbit eyes. The eyes were exposed to Ganzfeld illumination. Illumination was measured at three or four peripheral points at eccentricities up to 60 deg (human) or 90 deg (rabbit). Theoretical light-distribution curves were calculated from eye model data. Theoretical and experimental results for rabbit eyes agree within experimental errors. The experimental curve for human eyes shows a slightly steeper descent toward the periphery than the theoretical curve. Retinal illumination decreases only gradually toward the periphery in both human and rabbit eyes.