196 NATURES! UDY REVIEW [6:7-Oet., mo 



behind "bars'' of fly screen, leaving the enemy in possession oi 

 the great out-of-doors. For years I have thought that it is the 

 flies that ought to be put behind the ''bars" designed especially 

 for them, and not ourselves. 



A present solution of the problem takes for granted that all 

 windows and doors shall be screened, as before, and adds the 

 iinliftable burden of removing all filth at frequent intervals, or 

 •of storing it in fly-tight pits. I have just returned from a jour- 

 ne}' of several hundred miles, chiefly through the farming sections 

 ■of the Empire State. The hundreds of barnyards along the road, 

 with huge piles — in August — which looked as if a load had not 

 been hauled out of them since the barns were built, made the 

 above look like an arm-chair solution of the problem. Of course, 

 under any decent s}'stem of farming all this material ought to 

 have been put into the ground early in the spring ; but even with 

 that done and all the barnyard accumulations plowed under 

 weekly, or even daily during the summer, how about the miles 

 on miles of gutters, pastures, the city dumps, and necessary com- 

 post heaps in connection with every well-ordered suburban gar- 

 den? Even if all filth in which flies breed were properly cleaned 

 out of a city and used for fertilizer on the farms surrounding it, 

 would many of the eggs and maggots already developing in it be 

 killed in the operation ? 



I have no word to say against keeping premises intelligently 

 clean, but we must have fertilizer in large quantities and com- 

 post for our farms and gardens, and it has seemed to me that 

 the breeding places can not be for the filth fly the effective point 

 of attack. 



We need to know much more about the biology of the adult 

 insect, its favorite foods, its needs for water, its habits in seeking 

 shelter, the length of life and number of eggs and the distance 

 it flies or migrates from its breeding places. But what little we 

 do know indicates to me that the strategic point of attack is the 

 adult fly. We have long been working on this theory, unintelli- 

 gently and ineffectively, with sticky or poisonous fly paper and 

 traps ; but these means have only been employed to kill the few 

 flies that gained entrance to our houses. Carry the war into 

 Africa ; develop these means of attack seriously and effectively In 

 the out-of-doors, and I fully believe that there would be no filth 

 flies to go back to the compost heaps and barnyards to lay their 

 eggs. 



We were dining out on the porch, with the bobwhites, mead- 



