IN 1947 a young girl and her brother came to one of us (Benedict) for treatment of bilateral cataract. Both patients had had the cataracts since early childhood, and their condition had remained stationary. Although visual efficiency was impaired, especially in bright light, both children had progressed excellently in school and were not obviously handicapped. The cataracts were central only, the nucleus of the lens being clearly outlined as a gray disk and the periphery of the lens being clear. The children's mother had undergone needling for bilateral cataract in childhood, with somewhat disappointing results. The children's aunt exhibited the same gray nuclear cataracts without gross visual difficulty. Three years previously, in 1944, this aunt had brought her two sons (cousins of the children described above) to one of us (Benedict) for treatment, and their clinical records contained a description of bilateral nuclear cataract corresponding exactly with that of their