Parasites 



by some invisible thread. You make a move- 

 ment; and the Bombylius has disappeared. 

 You cast your eyes in search of her around 

 you, far away, judging the distance by the 

 vigour of her flight. There is nothing here, 

 nothing there. Then where is she? Close by 

 you. Look at the point whence she started: 

 the Bombylius is there again, hovering mo- 

 tionless. From this aerial observatory, as 

 quickly recovered as quitted, she inspects the 

 ground, watching for the favourable moment 

 to establish her egg at the cost of another 

 creature's destruction. What does she covet 

 for her offspring: the honey-cupboard, the 

 stores of game, the larvae in their transforma- 

 tion-sleep ? I do not know yet. What I do 

 know is that her slender legs and her dainty 

 velvet dress do not allow her to make under- 

 ground searches. When she has found the 

 propitious place, suddenly she will swoop 

 down, lay her egg on the surface in that light- 

 ning touch with the tip of her abdomen and 

 straightway fly up again. What I suspect, 

 ■for reasons set forth presently, is that the 

 grub that comes out of the Bombylius' egg 

 must, of its own motion, at its own risk and 

 peril, reach the victuals which the mother 

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