Ovary development of workers increased progressively with the following treatments: (a) with queen, with brood or without queen, with brood; (b) with queen (confined or free), without brood; (c) without queen, without brood.Ovary development of queenless, broodless workers separated from worker larvae (or pupae) by single or double screens was similar, but was significantly higher than that of queenright workers with brood (controls) and significantly lower than that of queenless, broodless workers; possibly a volatile brood (or brood-related) scent was acting to inhibit ovary development in these workers.