SummaryThe nutritional value forNannotrigona (S.) posticaworkers of mixtures of pollen from hives ofN. (S.) posticaandApis melliferawas tested by comparing ovary and hypopharyngeal gland development in groups fed different proportions of pollen from the two sources. A mixture of 75% pollen fromN. (S.) posticaand 25% pollen fromA. melliferawas a satisfactory substitute for 100%N. (S.) posticapollen.