INSECTS AND DISEASES 



413 



FIG. 164. Hodge fly trap. 



Traps. For the catching of adult flies there has recently 

 been devised by Dr. Hodge a new kind of trap. 

 He lays emphasis on the fact that about ten 

 days elapse after the 

 emergence of the fly be- 

 fore egg-laying begins. 

 Hence the most successful 

 line of attack will be to 

 catch the first flies that 

 emerge in the spring be- 

 fore they lay eggs. Each 

 fly caught then eliminates 

 thousands of flies that 

 might have descended 

 from this one during the 

 season. The general plan 

 of Dr. Hodge's trap is 

 much like the old-fash- 

 ioned traps, but it is used 

 in a different way. It is 

 placed over a hole in the 

 cover of a garbage can, 

 the cover is slightly lifted 

 so that the flies can enter 

 the can, then when they 

 seek to escape they are 

 caught in the trap. One 

 of these traps caught 2500 

 flies in less than an hour. 

 The flies may be killed by 

 submerging the trap in hot 

 water. Dr. Hodge writes 

 that a single trap has 



FIG. 165. A fly trap easily made. 



worked so successfully that he has not found it necessary 

 to put up screens on doors or windows. This trap is also 



