A colony of adult bees of known age which had already started brood-rearing was transferred to an isolated compartment on new pollen-free combs and fed only sugar syrup. Brood-rearing continued but for a relatively short period. For the production of the larval food, bees can use materials from their own body tissues, preferably those of the abdomen. The nitrogen content of the heads and thoraces of the emerging bees did not appreciably differ from those of bees fed a normal diet, but the nitrogen content of the abdomens was considerably lower. About as much nitrogen was used in the katabolism of the nurse bees and immature instars as was contained in the emerging bees which resulted.