EXCESS vitamin A ingestion increases bleeding tendency1, depresses basal metabolism2 and increases excretion of neutral 17-ketosteroids in urine of albino rats3. The Qo2 of liver slices of hypervitaminotic A rats is lower than that of control rats (Ray, Amal and Sadhu, D. P., unpublished observations), the weight of the thyroid is diminished and that of the adrenal increased2. In an attempt to elucidate the mechanism of hypometabolism induced in hypervitaminosis A, liver was studied for glycogen and fat contents and diaphragm as an index of glucose utilization in peripheral tissues.