Changes in the behaviour of honey-bees following their recovery from anaesthesia.

1. Chloroform anaesthesia did not impair the memory, change the foraging behaviour, or reduce the longevity of the treated bees; chloroform is therefore a satisfactory anaesthetic for use in experiments on bee behaviour. 2. Carbon dioxide anaesthesia did not impair the memory of treated bees, but it did induce a permanent change in their behaviour. Their pollen-collecting tendencies were either eliminated or suffered very marked reduction. Experiments with foraging bees of known age indicated that the carbon dioxide treatments had no direct effect on longevity. Treatment of recently emerged bees with carbon dioxide eliminated all or most of their brood-rearing and wax-secreting activities and caused them to forage at an early age. Foraging life is more hazardous than life within the hive, and therefore the expectation of life of these carbon-dioxide treated bees was less than that of the controls. 3. The effects of nitrogen anaesthesia were similar to those obtained with carbon dioxide. The factor common to both treatments is oxygen lack. 4. The theoretical and practicable possibilities of these results are discussed.