216 THE HOUSE FLY— DISEASE CARRIER 



on cool nights, he bases another Hne of attack, which 

 is to make a hole in the window screen, with the guid- 

 ing strips outside and the trap inside, thus catching 

 all the flies that attempt to enter the kitchen in that 

 way. He has tested this device, but thinks that it can- 

 not compete with the garbage-can trap. 



Professor Hodge (1910) points out that there is 

 much yet to be known about the biology of the adult 

 typhoid fly, its favorite foods, its needs for water, its 

 habits in seeking shelter, length of life, and the dis- 

 tance it flies, but he thinks that what little we know 

 indicates that the strategic point of attack is the adult. 

 He states that we have been long w^orking on this 

 theory unintelligently and ineffectively with sticky or 

 poisonous fly paper and traps, but that these means 

 have been employed only to kill the comparatively few 

 flies that gain entrance to our houses. 



"Carry the war into Africa; develop the means of 

 attack seriously and effectively in the out-of-doors, and 

 I fully believe that there will be no filth flies to go 

 back to the compost heaps and barnyards to lay their 

 eggs." After using his traps for a period, he found it 

 possible to dine on the porch; as he expressed it, he 

 had turned the tables on the flies, and put them in a 

 prison and let himself out. Hodge wishes to stimulate 

 invention towards making effective out-of-doors fly 

 traps, and he urges experiments with different baits. 

 He states that he did enough in the summer of 19 10 

 to be convinced that any country home "a half mile 

 away from its nearest ignorant neighbor, or any town- 



