The case history here presented, together with the striking family history of heredity, is regarded of sufficient interest for publication. George McI., aged 27, was referred to my Wills Hospital service, Nov. 2, 1914. The right eye had been lost from some unknown cause in childhood and presented a shrunken stump. If his statement is to be accepted, he had recently suffered a sudden and serious impairment of vision in the left eye, but the "vision had never been good." So far as he knew, the eye had not been subjected to any accident. Inspection revealed an aphakial eye with entire absence of the iris. No rudimentary trace of that membrane could be discovered. The retina was detached, and ruptured from before backward, the site of rupture being to the nasal side of the vertical meridian in the lower half of the globe. The vitreous was fluid and well filled