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CIRCULAR 9 7 7, U. S. DEPARTMENT OF AGRICULTURE 



centration is considerably higher than is usually needed for mosquito 

 control, the dust should be further diluted. This can be done in the 

 field with improvised mixing equipment if a suitable diluent is avail- 

 able. 





Figure 3.— Hand dusters: A, Plunger type; B, rotary type. 



