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insects as are able to eat, and, as the tent caterpillar, gypsy moth, 

 and many others of the same family have their mouth parts and 

 digestive system atrophied or rudimentary so that they do not eat 

 anything in the moth stage, they are not attracted to these traps nor 

 to any sources of food. There was not a single codling moth nor 

 borer of any kind taken in these traps during the season. Nearly 

 all of the lepidoptera or moths taken belong to the Noctuidae or cut- 

 worms which are for the most part injurious. The Diptera or flies 

 represented many different families, some of which are beneficial, 

 while others are injurious. A large percentage of ihem belong to 

 the Tachinidae or parasitic flies, and as the traps caught and des- 

 troyed so many of these insects which are our best friends, as they 

 destroy injurious insects, I am compelled to say that I believe the 

 traps did more harm than good. The number of parasitic flies cap- 

 tured during the season was much larger than the entire number of 

 injurious insects taken during the same time. 



As the majority of the injurious insects taken in these traps fly in 

 the night only, and most of the flies that are beneficial fly in the day- 

 time, I would advise those who use the traps to leave them out only 

 during the night, taking them in or having them closed during the 

 day, so that no insect can get into them. If this is done I think 

 they will prove very useful. 



EXPERIMENTS WITH PARIS GREEN ON APPLE TREES. 



In the fall of 1890, twelve apple trees were set out in the green- 

 house connected with the Insectary. This greenhouse is divided 

 into two sections iiy a partition across the middle, and six of the trees 

 were set out in the ground in each section. In the following spring 

 these apple trees had become well established, and on May 18, 1891, 

 the leaves being well grown, they were showered with Paris green in 

 water, in the proportion of one pound to 130 gallons of water. This 

 was applied with a Johnson pump and a No. 2 Nixon nozzle. 



