fea! 7 AOS. THE USURPER-BEE 65 
difference, unless the latter becomes disagreeably 
aggressive, and then all she does is to lift occasion- 
ally a warning leg, or to creep away and hide 
herself like a coward in the nest material. If the 
workers attack her, she tries to rub them off with 
her legs, and slips into a crevice between the 
clusters of cocoons, or into the nest material ; but, 
protected by her coat of mail, she has little 
cause to fear getting stung. 
Although the Pszthyrus during the first few days 
flies occasionally to and from the nest, I have seen 
no evidence that she brings home any food, or that 
she helps in any way to rear the Aomdéus brood. 
Her first care is to ingratiate herself with the 
inhabitants, and in this she succeeds so well that 
the workers soon cease to show any _ hostility 
towards her. Even the queen grows accustomed 
to the presence of the stranger, and her alarm 
disappears, but it is succeeded by a kind of de- 
spondency. Her interest and pleasure in her brood 
seem less, and so depressed is she that one can 
fancy she has a presentiment of the fate that awaits 
her. It is by no means a cheerful family, and the 
gloom of impending disaster seems to hang over it. 
But while the queen grows more dejected, the 
Psithyrus grows more lively, and takes an increasing 
interest in the comb, crawling about over it with 
unwonted alacrity, and examining it minutely. 
In June 1908 I had a good opportunity of 
watching a Ps. rupestris establish herself in one 
of my nests of &. dapedarius that I had placed in 
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