60 ENTOMOLOGICAL NEWS. [Feb., 'l6 



Several hundred of the larvae were collected and placed in 

 a glass jar having about two inches of damp sand in the 

 bottom. Within twenty-four hours all of the larvae had 

 burrowed beneath the surface of the sand, but not deep 

 enough to be seen on the bottom of the jar. None afterwards 

 went to the bottom. They apparently remained just out of 

 sight below the surface. The sand was not kept moist and in 

 a few days became very dry. No food was placed in the jar 

 until the seventh day after the larvae had been placed in it, 

 and then a small piece of decomposed beef, about one inch 

 square, was placed on top of the sand to determine whether 

 the larvae were ready to pupate or whether they would con- 

 tinue to feed. At the end of twenty-four hours all that re- 

 mained of the beef was the damp place which represented 

 its former position on the sand. No other food was placed 

 in the jar. 



The larvae did not cast their skins while pupating but 

 passed the pupal period within the larval skins, which re- 

 mained unbroken and but very little changed in appearance, 

 until time for the adult flies to emerge. The first adult emerg- 

 ed twenty-three days after the larvae were placed in the jar 

 and they continued to emerge as late as eighty-one days. It 

 was impossible to make a correct estimate of the pupal period 

 as they did not all begin to pupate at anywhere near the same 

 date and the period of emergence was so long. 



All of the several hundred larvae collected and bred out 

 were H. illuccns, no other species being present. No larvae 

 of any other dipterous families were found in the cadaver. 

 This, by the way, is remarkable, considering the number of 

 Chrysomyia macellaria, and other flies whose larvae are car- 

 nivorous, that are found in this region and which are always 

 ready to deposit their eggs in decaying animal matter. A de- 

 composed body, either human or animal, is a favorite breed- 

 ing place for C. macellaria, but not a single larva of this 

 species was found. It is not improbable that the larvae of 

 //. illuccns in such numbers were sufficiently predaceous to 



