“…Hospitals, Rochester, New York) (Received for publication March 3, 1938) Vitamin D has proved effective in raising the serum calcium and alleviating the symptoms of chronic parathyroprivic tetany in experimental animals (1, 2) and man (3,4,5). A number of factors including dosage (6,7), and calciumphosphorus content of the diet (8), have been found to influence its effect, and where these have not been taken into consideration vitamin D has failed (9,10).…”