Grade 1 and grade 2 ruby laser coagulations applied to the papillomacular bundle of the adult rhesus monkey eye and followed serially to six weeks revealed scarring limited to the pigment epithelium outer segments and occasionally outer nuclear layers of the retina. Laser coagulation in this area occasionally may be required in clinical situations. Based upon these experimental results, such a clinical use of ruby laser coagulation seems feasible and deserves further clinical investigation.