The Bumble- Bee Fly 



long as she does not become too importunate, 

 is quite readily tolerated by the caged Wasps. 

 None seeks to pick a quarrel with her. She is 

 even admitted to the table, the strip of paper 

 smeared with honey. But she is doomed if 

 she inadvertently sets foot upon the combs. 

 Her costume, her shape, her size, which tally 

 almost exactly with the costume, shape and 

 size of the Wasp, do not save her from her 

 fate. She is at once recognized as a stranger 

 and attacked and slaughtered with the same 

 vigour as the larvse of the Hylotoma Saw-fly 

 and the Saperda Beetle, neither of which bears 

 any outward resemblance to the larva of the 

 Wasps. 



Seeing that identity of shape and costume 

 does not save the Polistes, how will the Volu- 

 cella fare, with her clumsy imitation? The 

 Wasp's eye, which is able to discern the dis- 

 similar in the like, will refuse to be caught. 

 The moment she is recognized, the stranger 

 is killed on the spot. As to that there is not 

 the shadow of a doubt. 



In the absence of Bumble-bee Flies at the 

 moment of experimenting, I employ another 

 Fly, Milesia fidminans, who, thanks to her 

 slim figure and her handsome yellow bands, 

 presents a much more striking likeness to the 



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