might presumably occur as a result of old age, or through injuries received 

 in colliding with the sides of the cage in a desperate attempt to escape. 



Fiff. 4. Part of laboratory apparatus used in the feeding work. 



In order to determine the actual death rate resulting from such 

 causes, 48 bees were placed in a screen cage alongside the poisoned ones, 

 and kept well supplied with unpoisoned syrup (See Fig. 4). None of the 

 bees in this cage died during a period of nearly four days. This was fully 

 three days after all the bees were dead in the cages containing poisoned 

 syrup. At the end of this period, the cage was lifted, and all the bees fed 

 on pure syrup flew away. 



Fig-. 5. Mercuric cliloride papers sliowing* tests from known amounts of arsenic. Arsenic 

 caused the papers to turn yellow. In the picture it shows dark. 



