FLIES AND OTHER HOUSEHOLD INSECTS 



25 



nearest available breeding place. Occasionally hosts of these 

 insects invade Nev^ York city to the great discomfort of the 

 residents. 



Control. The control of this species is practicable though at 

 the outset it appears somewhat difficult. All that is necessary is to 

 provide drainage so that pools of v^ater will not stand more than 

 a few days. This is accomplished by running narrow ditches 

 within about 25 feet of the headland and 40 or 50 feet apart, all 

 being connected with some tidal creek so that they are flushed out 

 twice daily. The walls of the ditches should be perpendicular and 

 the bottom at a uniform level. Experience has shown it inad- 



/ 



\ 



v 



\ 



Fig. 9 Salt marsh mosquito from above, the toothed front claw more enlarged. 

 (After Howard, U. S. Dep't Agric. Div. Ent. Bui. 25. n. s. 1900) 



visable to have the walls sloping or to attempt to secure a uniform 

 pitch, since the latter almost invariably results in pools not reached 

 by the daily tides. This work has been conducted on an extensive 

 scale in the vicinity of New York city with most gratifying results. 

 Several types of ditching machines are in use and the work is 

 comparatively inexpensive. 



The elimination of mosquito breeding places on the salt marshes 

 may sometimes be accomplished by the use of tidal gates and a 

 series of drains. This method, while thoroughly effective, belongs 

 to the domain of land development rather than to that o( insect 



