l68 NEW YORK STATE MUSEUM 



the i6th was a revelation. Insects of five orders in astonishing 

 numbers had transformed beneath it, and were assembled under 

 the ridge cord, waiting to be picked off. There were several square 

 feet of Chironomidae in the top, and stone flies and crane flies 

 and caddis flies and May flies were scattered all over the sides. 



We found the gathering of all these specimens no inconsiderable 

 task. It required usually aiore than an hour's diligent application 

 for two of us every time. And this, added to other matters we 

 had in hand, left us no time for investigating the relations these 

 insects bear toward each other in the stream bed before their 

 transformation. This account, therefore, of the insect life of 

 Beaver Meadow brook is to be considered as a mere preliminary 

 statement, giving only such data as were obtained with the aid of 

 this tent trap. We believe that this trap will yield quantitative 

 results within its proper field (winged insects with aquatic larvae) 

 and that it is the first to be devised that is of any value for quanti- 

 tative purposes. And we believe furthermore, that this collecting 

 method is one of wider applicability. We think, for instance, that 

 a water tent may be used for positive determination of the breed- 

 ing grounds of various kinds of mosquitos, and of the relative 

 numbers in which each kind is produced. 



The yield of the winged insects from this area six feet square of 

 brook bottom is shown in the following table '} 



^ I have recently made an improvement in the construction of the tent 

 trap — one that greatly economizes the labor of taking out the catch. I 

 make it now in pyramidal form with opaque sides supported on a srlid 

 frame, but with a hole at the top, over which I place a light bag of netting. 

 The insects crawl up into this bag, which being detachable, may be ex- 

 changed in a moment for another, and with all its contents inserted into a 

 large cyanide bottle. 



