In 1924 Fisher1 and Allan, Bowie, Macleod and Robinson2 reported that completely depancreatized dogs adequately treated with insulin usually failed to survive more than two to three months. At autopsy the most prominent change observed was an extensive fatty infiltratration and degeneration in the liver. In general these findings have been widely confirmed. Occasional animals have been observed in which the fatty changes developed and death occurred in five to six weeks, while others have survived for six months to a year and still others have failed to show any evidence of disease of the liver and have survived for long periods with no supplementary treatment other than the insulin therapy. The latter constitute a small minority and will be discussed later. The addition of raw pancreas to the diet of the depancreatized dog was found by Allan, Bowie, Macleod and Robinson to prevent or relieve the fatty