96 The Control of Mosquitoes 



work on the windward side was ineffective, and the 

 influx of Anopheles albimanus increased. Work in 

 this swamp was then stopped and the force con- 

 centrated in a larvae-infested portion of the Ancon- 

 Corozal swamp about a mile south of Corozal. 

 Since the latter area has been controlled no large 

 influx of Anopheles has taken place at Corozal, 

 except during short periods when the wind changed 

 and blew from south to north. 



The large swamp between Corozal and Mira- 

 flores was difficult to control in a satisfactory- 

 manner. It was neglected for a certain time to 

 ascertain if, when producing Anopheles at its 

 maximum capacity, many of them would reach 

 Corozal, traveling with the wind. Apparently 

 this did not happen, as the number of adults at 

 Corozal did not increase while the other area a mile 

 to the south of Corozal was kept under proper 

 control. 



Soon after the Corozal-Miraflores area was 

 purposely neglected the catch at the laborers' 

 barracks at Miraflores increased and the influx 

 continued. The maximum catch in a single trap 

 on one night was more than a thousand. This 

 trap was attached to an 8" x 24" opening in the 

 screening and the total area of small openings in 

 the trap screen through which mosquitoes passed 



