THE BLUEBOTTLE in 



would influence the decision of a mother obliged to lay 

 her eggs under exceptional conditions. With this object 

 in view, I employed small jars, each baited with a bit of 

 butcher's meat. The respective lids were made of dif- 

 ferent-colored paper, of oil-skin, or of some of that tin- 

 foil, with its gold or coppery sheen, which is used for 

 sealing liqueur-bottles. On not one of these covers did 

 the mothers stop, with any desire to deposit their eggs; 

 but, from the moment that the knife had made the narrow 

 slit, all the lids were, sooner or later, visited and all, 

 sooner or later, received the white shower somewhere 

 near the gash. The look of the obstacle, therefore, does 

 not count; dull or brilliant, drab or colored: these are 

 details of no importance; the thing that matters is that 

 there should be a passage to allow the grubs to enter. 



Though hatched outside, at a distance from the coveted 

 morsel, the new-born worms are well able to find their 

 refectory. As they release themselves from the egg, 

 without hesitation, so accurate is their scent, they slip 

 beneath the edge of the ill-joined lid, or through the pass- 

 age cut by the knife. Behold them entering upon their 

 promised land, their reeking paradise. 



Eager to arrive, do they drop from the top of the wall? 

 Not they! Slowly creeping, they make their way down 

 the side of the jar; they use their fore-part, ever in quest 

 of information, as a crutch and grapnel in one. They 

 reach the meat and at once install themselves upon it. 



Let us continue our investigation, varying the condi- 

 tions. A large test-tube, measuring nine inches high, is 

 baited at the bottom with a lump of butcher's meat. It 



