Screening and Destruction 213 



darkest nooks in the room ; in remote dark corners, 

 behind various objects on the wall, and under 

 window ledges, etc. Careful search is required 

 to find them and on a dark colored wall they are 

 almost invisible. 



In the early morning hours soon after daybreak, 

 and in the twilight hour of the evening, Anopheles 

 usually collect on the screening of verandas, 

 doors, and windows, and are more easily caught 

 than when indoors. The chloroform tube does 

 not work very well on screening and the "slapper" 

 is employed. 



The cost of mosquito catching in dwellings is 

 very slight. We employed common laborers at 

 ten cents an hour. One man can cover a score 

 of barracks in two or three hours. If the houses 

 are in a group, an experienced mosquito catcher 

 will examine as many as twenty in three hours. 

 Of course, the number of houses covered depends 

 on their size, the number and interior arrangements 

 of the rooms, the number of mosquitoes found, 

 and the distance from one house to another. 

 The statement made above regarding the number 

 of houses a man can examine, refers to the standard 

 barrack of the Canal Zone, a one-room, one-story 

 building about forty by sixty feet. 



In the early part of 191 1 hand catching was 



