The inheritance and some developmental effects of a new allele of ocular retardation (orJ) are described. Affected animals or 12 days of gestation, show reduced cell death in the eye cup and thickening of the inner wall of the optic fissure. At 11 to 13 dyas of gestation orJ/orJ eyes grafted to the testis do not produce retina as their orJ+ littermates do. Adult animals have small eyes with closed lids, abnormal retinal layers, and no optic nerve.