The Life of the Fly 



brown shell, the substance of the maggot has 

 disappeared, changed Into a restless swarm. 



There are thirty-five occupants. I replace 

 them in their casket. The rest of my harvest, 

 wherein, no doubt, are other pupae similarly 

 stocked, is arranged in tubes that will easily 

 show me what happens. The thing to dis- 

 cover Is what genus of parasites the grubs 

 enclosed belong to. But It Is not difficult, 

 without waiting for the hatching of the 

 adults, to recognize their nature merely by 

 their mode of life. They form part of the 

 family of Chalcldldas, who are microscopic 

 ravagers of living entrails. 



Not long ago. In winter, I took from the 

 chrysalis of a Great Peacock Moth four hun- 

 dred and forty-nine parasites belonging to the 

 same group. The whole substance of the fu- 

 ture Moth had disappeared, all but the 

 nymphal wrapper, which was intact and 

 formed a handsome Russia-leather wallet. 

 The worm-grubs were here heaped up and 

 squeezed together to the point of sticking to 

 one another. The hair-pencil extracts them 

 In bundles and cannot separate them without 

 some difficulty. The holding-capacity Is 

 strained to the utmost; the substance of the 

 vanished Moth would not fill It better. That 

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