June, '131 WASHBURN: ROACH TRAP 329 



Very young roaches can pass through the wire mesh of the Hodge 

 Fly Trap. 



The statement is made above that the hairs appeared to be unneces- 

 sary. We found by observation that when the Graham Trap is placed 

 in a secluded part of the room frequented by roaches, where it is not 

 likely to be disturbed, there is little or no effort on the part of the 

 insects to escape and the trap can be left unattended for possibly 

 several days; on the other hand, if the trap was placed where light 

 reached it in the morning and there was more or less activity and noise 

 near it, the insects escaped under those conditions and the hairs made 

 it somewhat more difficult for them to get out. Very few adult roaches 

 are caught in the day time, but nymphs of all sizes enter the trap, 

 apparently at all hours of the day. 



We append some of the catches, indicating what the Graham Trap 

 accomplished : 



March 22 In 2 hours 30 Nymphs captured in Graham Trap. 



" 24 " 5 " o Adults and 16 young. 



" 24-2.5 25 " " 15 



" 25 " day time 5 " " 17 X\'mphs — different stages. 



April 1 19 " " 5 



In another Graham Trap same day 40 Adults and 12 Nymphs 

 Under Sink 10 " " 1 "Silver Fish" 



The last three traps were set over night 

 April 14 14 " " 44 Nymphs 



10 5 " " 54 " 



It occurred to the Avriter that, in view of the lack of success with 

 many traps and the very marked success with the Graham Trap, the 

 above was worthy of record. That the Hodge Fly Trap is useful in 

 this connection, however, is evidenced by observations on the part of 

 Mr. Williamson of this Division, upon two traps, baited with milk 

 which was freciuently renewed, placed in the kitchen of a steam-heated 

 flat. The results are shown in the following table: 



