Juvenile amaurotic idiocy (Vogt-Spielmeyer's disease) was first recognized in 1826 by Stengel,1 a Norwegian physician. The descriptions of Batten,2 Vogt,3 and Spielmeyer4 some 50 years ago, clearly established the basic clinical and pathological aspects of the disease and, 25 years later, thorough study of a large number of cases which were observed in Sweden5,6 contributed much to the genetic, clinical and pathological understanding of the disease. In this country, juvenile amaurotic idiocy seems to have attracted much less attention than the infantile type (Tay-Sachs' disease) and only a few reports are available in the medical literature. Yet the disease is not as rare as commonly thought. In fact, from personal observation, the incidence of the juvenile form (9 cases) is not far off from the incidence of the infantile form (15 cases). This ratio of 6:10 was observed in a hospital where there is a