The histopathologic response of the chorioretinal tissue of rabbits to argon-ion and krypton-ion laser radiation at wavelengths of 6471Å, 5682Å, 5308Å, 4880Å and 4579Å was determined. The effects of incident energy at these wavelengths at intervals of one, seven, and 21 days were evaluated by microscopy. © 1969.