The Life of the Fly 



learn more about it later, under conditions that 

 make examination easier. 



The beak of the bird invaded was closed at 

 the start, as far as the natural contact of the 

 mandibles allowed. There remained a narrow 

 slit at the base, sufficient at most to admit the 

 passage of a horse-hair. It was through this 

 that the laying was performed. Lengthening 

 her ovipositor like a telescope, the mother in- 

 serted the point of her implement, a point 

 slightly hardened with a horny armour. The 

 fineness of the probe equals the fineness of the 

 aperture. But, if the beak were entirely 

 closed, where would the eggs be laid then? 



With a tied thread, I keep the two mandi- 

 bles in absolute contact; and I place a second 

 Bluebottle in the presence of the Linnet, which 

 the colonists have already entered by the beak. 

 This time, the laying takes place on one of the 

 eyes, between the lid and the eye-ball. At the 

 hatching, which again occurs a couple of days 

 later, the grubs make their way Into the 

 fleshy depths of the socket. The eyes and the 

 beak, therefore, form the two chief entrances 

 into feathered game. 



There are others ; and these are the wounds. 

 I cover the Linnet's head with a paper hood 

 which will prevent invasion through the beak 

 320 



