A Parasite of the Bembex 



corner of the house among the pupae of its 

 more fortunate companions. Its end may be 

 more cruel still. Should the provisions fail, 

 should the mother-nurse delay too long in re- 

 turning with food, the Flies devour the larva 

 of the Bembex. I verified this black deed by 

 rearing the brood myself. All went well so 

 long as there was plenty to eat; but, if the 

 daily portion was omitted by accident or de- 

 sign, next day or the day after I was sure to 

 find the Fly's grubs greedily slicing up the 

 larva of the Bembex. So, when the nest is 

 invaded by the parasites, the lawful larva is 

 doomed to perish, either by hunger or by a 

 violent death; and this is what makes the 

 Bembex hate the sight of the Miltogrammae 

 prowling around her home. 



The Bembex are not the only victims of 

 these parasites : all the Digger-wasps without 

 distinction have their burrows plundered by 

 Tachinae and especially Miltogrammae. Dif- 

 ferent observers, notably Lepeletier de Saint- 

 Fargeau, have spoken of the wiles of these 

 bold-faced Flies; but none of them, so far as 

 I know, has remarked this very curious In- 

 stance of parasitism at the expense of the 

 Bembex. I say very curious, because the 

 conditions are quite different. The nests of 

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