Preventive Measures 307 



grass is not allowed near settlements, as water con- 

 tainers may become hidden under it. Interiors of 

 houses are inspected to detect mosquito-producing 

 containers, and tenants are invited to complain 

 to the district sanitary inspector when mosquitoes 

 are noted indoors. All houses are inspected for 

 Anopheles at frequent intervals, at which times a 

 keen search is also made for Aedes calopus. When 

 adults of this species are noticed, very thorough 

 inspection is made of all houses and yards in the 

 vicinity. Each week the district inspector reports 

 the number of Aedes calopus breeding places found 

 during the regular weekly inspection, and notes 

 their location in the station diary. As his district 

 is inspected by the division inspector, the assistant 

 chief sanitary inspector, and the chief sanitary 

 inspector, any neglect of duty is soon detected. 

 As a matter of fact, Aedes calopus are now very 

 scarce near the settlements where the non-immunes 

 live or spend their time. 



Attention is also given to movable containers. 

 Whenever any large machinery or new supplies 

 are moved into a district, they are inspected for 

 parts capable of containing rain or other water. 

 It has been found that certain types of tanks on 

 locomotives and parts of certain dump cars hold 

 rain water, and are capable of breeding ^eJe^ 



