112 THE WONDERS OF INSTINCT 



is closed with wire-gauze, whose meshes, two millimeters 1 

 wide, do not permit of the Fly's passage. The Blue- 

 bottle comes to my apparatus, guided by scent rather than 

 sight. She hastens to the test-tube, whose contents are 

 veiled under an opaque cover, with the same alacrity as to 

 the open tube. The invisible attracts her quite as much 

 as the visible. 



She stays awhile on the lattice of the mouth, inspects 

 it attentively; but, whether because circumstances failed 

 to serve me, or because the wire network inspired her 

 with distrust, I never saw her dab her eggs upon it for 

 certain. As her evidence was doubtful, I had recourse 

 to the Flesh-fly (Sarcophaga carnaria). 



This Fly is less finicking in her preparations, she has 

 more faith in the strength of her worms, which are born 

 ready- formed and vigorous, and easily shows me what 

 I wish to see. She explores the trellis-work, chooses a 

 mesh through which she inserts the tip of her abdomen, 

 and, undisturbed by my presence, emits, one after the 

 other, a certain number of grubs, about ten or so. True, 

 her visits will be repeated, increasing the family at a rate 

 of which I am ignorant. 



The new-born worms, thanks to a slight viscidity, 

 cling for a moment to the wire-gauze; they swarm, 

 wriggle, release themselves and leap into the chasm. It 

 is a nine-inch drop at least. When this is done, the 

 mother makes off, knowing for a certainty that her off- 

 spring will shift for themselves. If they fall on the 



1 .078 inch.— Translator's Note. 



