The morphologic features of corneal lesions produced in rabbits by human herpesviruses, types 1 and 2 (HH1 and HH2), were studied using light and electron microscopic techniques. Also, healing lesions produced by the HH1 virus and treated by idoxuridine were similarly investigated. Scanning electron micrographs showed that although the morphology of HH1 and HH2 lesions was similar in most respects. HH2 lesions typically were raised, whereas the edges of HH1 lesions were not elevated above the corneal surface. In both HH1 and HH2 lesions, infected epithelial cells first separated from neighboring cells, then became globular, and finally were removed, leaving a central excavation. During healing of HH1 lesions, normal epithelial cells invaded the central crater from all sides to cover damaged cells and reconstitute the epithelial surface.