FLOWER-FLIES. 615 



appear in houses in July, becomes exceedingly aoundant 

 in September, and does not disappear till killed by cold 

 weather. It is probable that, like the domestic fly of Europe, 

 it lays its eggs in dung, in which its larvae live, and pass 

 through their changes of form. The Americans are accused 



o o 



of carelessness in regard to flies, and apparently with some 

 reason. But if these filthy, dung-bred creatures swarm 

 in some houses, covering every article of food by day, and 

 absolutely blackening the walls by night, in others com- 

 paratively few are found ; for the tidy housekeeper takes 

 care not to leave food of any kind standing about, uncovered, 

 to entice them in, and makes a business of driving out the 

 intruders at least once a day. If a plateful of strong green 

 tea, well sweetened, be placed in an outer apartment acces- 

 sible to flies, they will taste of it, and be killed thereby, as 

 surely as by the most approved fly-poison. In the first 

 volume of " The Transactions of the Entomological Society 

 of London," Mr. Spence gives an account of a mode of ex- 

 cluding flies from apartments, which has been tried with 

 complete success in England. It consists of netting, made of 

 fine worsted or thread, in large meshes, or of threads alone, 

 half an inch or more apart, stretched across the windows. 

 It appears that the flies will not attempt to pass through 

 the meshes, or between the threads, into a room which is 

 lighted only on one side ; but if there are windows on another 

 side of the room they will then fly through ; such windows 

 should therefore be darkened with shutters or thick curtains. 

 The An thorny ians, or flower-flies (AXTHOMYIAD.E), are 

 easily distinguished from the preceding flies, which they 

 otherwise resemble, by the smaller size of their winglets, 

 and by the mesh in the middle of their wings, which is 

 long, narrow, and open at the end. They are smaller in- 

 sects than the foregoing, their flight is more feeble, their 

 wings, when at rest, do not spread so much, and the bristle 

 on the last joint of their antennae is not often feathered. 

 Most of them frequent flowers, and are sometimes seen 



