M()S()rii"()Ks 



1 •{•> 



Methods of extermination. It is luiiuiiiiic Inr us in nur work 

 of exterininatini;' iiiostiuilofs that tlicv pass tliL* fust ilirce 

 stages of life in water, and that the achilts innst conic to water 

 to lay tlieir ej^gs, that is, nios(niitoes are strictly dependent 

 upon suitable breeding- waters, in all 

 successful campaigns undesirable [xxils 

 in which mosquitoes may brec^d liave 

 been drained or tilled. Streams and 

 ponds have had their shores cleane(l of 

 weeds, bi'ush, and stumps, and haxc 

 been graded so that ])ools were not 

 left in which mostpiiloes could brei'(l 

 aft(M' fi'cshets and storms. Tlien they 

 have been stocked with lishes which 

 feed u})on the young of mosquitoes. All 

 water which was too tem[)()rary to drain 

 or too polluted for fishes has been cov- 

 ered with crude petroleum (one ounci- 

 to fifteen square feet of surface). This 

 treatment has been repeated as ohou as 

 wrigglers have appeared. A mos(iuito 

 can walk on the surface of water l)ut it 

 cannot stand on oil ; hence, as all mos- 

 ([uitoes come to the near-by water to lay 

 their eggs, they soon perish, rrecautions 

 liave been taken not to allow water to 

 stand in tubs, barrels, or cisterns with- 

 out being covered insect-tight. 



I'hrough systematic ap})licatiou of 

 these methods, Tanama, Cuba, New Orleans, aiul many citifs 

 in the north have effectually rid themselves of mosquitoes. 

 The results of these campaigns ju'ove that the e.vierminalion 

 of the mosquito from any locality is no longer a matter (»f 

 doubt or experiment. 'Hirough drainage of salt marshes whole 



I-K.. To. .lam hottlc iiiiii 



UiiiiltU'r arran«;f(l so ju* 



to secure t'i(^s of a single 



in(»si{uito 



