A BEE-HUNTER 17 



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proof. The carnivorous grub is killed by honey. Is 

 the honey-fed grub, inversely, killed by carnivorous 

 diet ? Here, again, we must make certain exceptions, 

 observe a certain choice, as in the previous experiments. 

 It would obviously be courting a flat refusal to offer a 

 heap of young crickets to the larvae of the Anthophorus 

 and the Osmia, for example ; the honey-fed grub would 

 not bite such food. It would be absolutely useless to 

 make such an experiment. We must find the equivalent 

 of the bee smeared with honey ; that is, we must offer 

 the larva its ordinary food with a mixture of animal 

 matter added. I shall experiment with albumen, as 

 provided by the egg of the hen ; albumen being an 

 isomer of fibrine, which is the principal element of all 

 flesh diet. 



Osmia tricornis will lend itself to my experiment 

 better than any other insect on account of its dry honey, 

 or bee-bread, which is largely formed of flowery pollen. 

 I knead it with the albumen, graduating the dose of the 

 latter so that its weight largely exceeds that of the bee- 

 bread. Thus I obtain pastes of various degrees of con- 

 sistency, but all firm enough to support the larva without 

 danger of immersion. With too fluid a mixture there 

 would be a danger of death by drowning. Finally, on 

 each cake of albuminous paste I install a larva of medium 

 growth. 



This diet is not distasteful ; far from it. The grubs 

 attack it without hesitation and devour it with every 

 appearance of a normal appetite. Matters could not 

 go better if the food had not been modified according 

 to my recipes. All is eaten ; even the portions which I 

 feared contained an excessive proportion of albumen. 



