ADDITIONAL NOTES 277 



the cell. Sometimes she constructed two cells in different 

 places at the same time, and then, while she laid her eggs 

 in the one, the lapidarius workers, amid much quarrelling, 

 would often seize the opportunity to lay their eggs in the 

 other. After she had finished guarding her own eggs she 

 demolished the cell containing the lapidarius eggs. She 

 was heard to utter the mournful cry (p. 252) on many 

 occasions. On July 23 I removed her from the nest for 

 four hours to let the workers finish laying eggs in a cell 

 which she had begun and they had built up, but when I 

 put her back the workers attacked her and stung her to 

 death. Although she had laid a batch of eggs only a 

 quarter of an hour before she was removed, the workers 

 did not molest them. It may be the Psithyrus kneads 

 a distasteful saliva into the wax covering her eggs. 



On another occasion, a strong lapidarius nest in which 

 a rupestris queen had been reigning for eleven days was 

 overturned. The shock of the accident seemed to unnerve 

 the Psithyrus, for she wandered aimlessly about the nest, 

 and two hours later the workers mobbed her and stung 

 her to death. It appears that when the colony is populous 

 the rupestris will lose her life unless she maintains con- 

 tinuously her rule of repression. 



On July 20 I put a searching rupestris queen into the 

 vestibule of a lapidarius nest containing about 80 workers. 

 She passed into the nest without hesitation and imme- 

 diately produced an uproar, the workers and their queen 

 rushing hither and thither in great excitement. The 

 excitement died down in about twenty minutes, and on 

 lifting the nest I found the Psithyrus in a dying condition 

 with six workers attached to her trying to sting her and 

 thirteen dead workers lying around her. A few days later 

 I found in this nest a female of the deadly parasitic moth 

 Aphomia soeiella, and another of the deadly fly Brachycoma 

 devia, but the humble-bees paid not the slightest attention 

 to them. 



