The Bumble-Bee Fly 



spite of its exceeding cleanliness, this grub is 

 not exempt from the physiological ills insepa- 

 rable from the stomach. Like all that eats, it 

 has intestinal waste matter with regard to 

 which its confinement compels it to behave 

 with extreme discretion. Like so many other 

 close-cabined larvse of Wasps and Bees, it waits 

 until the moment of the transformation to rid 

 itself of its digestive refuse. Then, once and 

 for all, it casts out the unclean accumulation 

 whereof the pupa, that delicate, reborn organ- 

 ism, must not retain the least trace. This is 

 found later, in any empty cell, in the form of 

 a dark-purple plug. But, without waiting for 

 this final purge, this lump, there are, from time 

 to time, slight excretions of fluid, clear as 

 water. We have only to keep a Wasp-grub in 

 a little glass tube to recognize these occasional 

 discharges. Well, I see nothing else to explain 

 the action of the Volucella's grubs when they 

 dip into the cells without wounding the larvae. 

 They are looking for this liquid, they provoke 

 its emission. It represents to them a dainty 

 which they enjoy over and above the more 

 substantial fare provided by the corpses. 



The Bumble-bee Fly, that sanitary inspector 

 of the Vespine city, fulfils a double office : she 



wipes the Wasp's children and she rids the 



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