MOSQUITO CONTROL 288 



undoubtedly some of the volatile oils are also, although the literature 

 speaks only in general terms on this subject. 



Destruction of Adult Mosquitoes 



Howard, D^'ar and Knab, and also Hegh, cite various methods of 

 destruction of adult mosquitoes in dwellings, such as puffing powdered 

 P3'rethrum into nooks frequented by mosquitoes, fumigation by burning 

 pyrethrum, sulphur or cyanide fumigation, vapors of cresyl and of creo- 

 line. Le Prince and Orenstein describe a labyrinth trap for windows, 

 quite similar to the Hodge window fly trap. Hegh figures and describes 

 other fly traps. 



PROTECTION FROM MOSQUITOES 



Protection of Dwellings from Mosquitoes 



In mosquito sections the screening of all habitations against mos- 

 quitoes is essential. This must be done thoroughly and the screens must 

 be carefully examined and repaired. When holes or openings occur in 

 the screening, the mosquitoes enter and are trapped and the building is 

 often worse off than if unscreened. 



For protection against Anopheles alone, a 16-mesh wire screen is 

 sufficient, but small Aedes can pass through this and therefore 17 or 

 18-mesh is necessary. Le Prince and Orenstein give the specifications for 

 the 18-mesh screen to be of 90 per cent pure copper and not more than 

 one-half of one per cent of iron for damp tropical countries, the gauze 

 having eighteen strands of wire of one one-hundredth of an inch diameter 

 in each linear inch. The best type of screen for salt or acid air will 

 probably be a screen coated with an acid proof, noncorrosive alloy such 

 as Gageite. In many parts of the United States other types of wire 

 screening are thoroughly efficient. ~ 



Where mosquitoes are abundant the double door vestibule arranged 

 so that the two doors can not be opened at the same time is highly 

 desirable when practicable. In tropical countries with verandas around 

 the entire house, the entire screening of the verandas is essential. Lieut. 

 Brigham (1918) describes an ingenious mosquito electrocuter. 



Protection of the Individual 



Campers are in the habit of using almost anything that will make a 

 dense smudge to drive away mosquitoes. The fumes of burning pyrethrum 



* Mr. F. C. Bishop has for several years been making tests of serviceability of many 

 types of screening in various parts of the country, and although he has not submitted 

 a final report, will gladly advise any one desiring this information for official purposes. 

 His address is Box 208, Dallas, Texas. 



