59^ 



HOWARD 



which was bred in Washington, on June i6, in large numbers 

 from miscellaneous fasces of unknown age collected June 13. 

 It was also bred from excrement taken from the sinks of the 

 militia camp at Leesburg, Virginia, in July. 



Spkcerocera -pusilla Meig. 



The insects of this genus resemble the foregoing both in 

 structure and in habits. The larvae are recorded in Europe as 

 feeding in horse dung and cow dung, and one species accord- 

 ing to Signoret has been 

 found on scale-insects. The 

 present species is European, 

 recognized here by Mr. Co- 

 quillett. It was reared May 

 20 from fresh excrement col- 

 lected May 12, giving a very 

 short period of development. 



Fig. 36. Sphcerocera subsnllans — eu 

 larged (original). 



SphcBi'ocera suhstdtans Fabr. 



This is also a European 

 species recognized here by 

 Mr. Coquillett. It was reared 

 with the foregoing species 

 upon the 20th of May, from 

 excrement deposited Ma}' 12. 

 The same species swarmed 

 upon a deposit during a storm 

 which occurred on June 12. It was captured on other dates 

 in May and in July at Washington by both Messrs. Pratt 

 and Busck. 



Family SYRPHID^F:. 



The species of this family, the majority of which are flower 

 flies, are among the most numerous and best known flies. They 

 abound in gardens in sunny weather. The larvre are variable 

 in habits, many being predator}^, feeding upon soft bodied in- 

 sects, while others live in foul water or in decaying vegetable 



