REPORT OF CASE History. —Early in August, 1927, a servant girl, aged 23, was admitted to the medical clinic of the University Hospital at Groningen, Holland, because her physician could not find an appropriate diet after having treated her for three years for a condition he thought was diabetes. Backache was the complaint which led the girl to see a physician, and he had found reducing properties in her urine. At that time, the patient had been drinking a good deal, the quantity of urine passed was abundant and the appetite was normal. A diet was prescribed, from which sugar and sweet foodstuffs were omitted, with potatoes and bread in moderate quantities. The backache disappeared, but the urine was not always sugar-free. The physician further informed us that the urine passed at night never contained any sugar, while that passed during the day at times showed reducing properties. About a