PHOTIC REACTIONS OF HONEY-BEE 359 



the animals were feeding. Each wingless individual was then 

 confined in a small cylindrical cage of screen wire, the bottom of 

 which was formed by a layer of tissue-paper over cotton to pre- 

 vent injury in case of falling. In the same cage were also placed 

 two friendly winged workers to counteract any possible effects 

 of isolation. The cages of bees were kept in a darkened box when 

 not directly under experimentation, since the influence of light 

 often caused the animals to maintain a restless activity which 

 appeared, in some cases, to shorten life considerably. In the 

 dark, however, they usually remained more quiet. 



Each cage was supplied with water by a small wad of saturated 

 cotton placed on its top. Small quantities of honey were also 

 supplied on short wooden sticks stuck to the side of the cage. 

 Early in the morning, at noon, and in the evening the cages 

 were cleaned by removing excess honey, etc., and fresh honey 

 and water were provided. Such operations were carried out at 

 least a half-hour before any trials were made on the animals. 



The temperature of the laboratory in most of the experiments 

 was kept above 20° to 21°C. This was found to be an important 

 consideration, since at lower temperatures bees became torpid 

 and inactive. In collecting the animals even, an attempt was 

 made to take them on warm, sunny days which had, in general, 

 been preceded by warm weather. It was found that bees brought 

 in after a brief period of cold, wet weather were apt to be either 

 unresponsive or extremely variable in their behavior. 



2. Blackening the eye 



Any technic for blackening the eye of a wingless bee requires, 

 of course, the use of an anaesthetic. In the present experiments 

 ether was used exclusively. Care was taken to administer it 

 rather slowly and in minimal doses. When completely anaes- 

 thetized, the bee was placed on one side, on a small cork pinning 

 board. Here it was fastened down securely by the use of insect 

 pins, with which the thorax, abdomen, and legs were securely 

 braced against the cork. The blackening was then applied to the 

 eye, the entire surface being covered with as thick a coat as pos- 



