AQUATIC INSECTS IN THE ADIRONDACKS 4OI 



coarsest of which had a mesh of about 2.5 mm square (10 meshes to 

 the inch). The method was the same for both: the plot was staked 

 out; the vegetation was swept with an air net down to the water Hne for 

 its aerial forms of life ; it was swept again with a water net for its aquatic 

 population; it was then pulled up by the roots and piled in pails and 

 examined a handful at a time in a bowl of clean water, having all the 

 animal Hfe separated from it ; the soil of the bottom was then scraped 

 up and sifted for a depth of two or three inches. The material was very 

 quickly gathered up from the plot selected, but the separation of the 

 aninial life from the plants and debris was a whole day's work for two 

 or three persons, to say nothing of the time necessary for studying the 

 animals later. These studies, though time-consuming, always yielded 

 the information sought as to the relative numbers of the several species 

 present, and were profitable, also, in quite another way. The careful 

 examination of the situation which they necessitated always revealed the 

 presence of a number of species not found by more superficial collecting 

 methods, and these were not always the smaller species. 



First plot. This was in the creek just below the hatchery. The site 

 is shown in plates 4 and 5. The plot extended from the edge of the 

 current in open water 12 to 15 inches in depth, to the bank, a distance 

 of about 5 feet, and a strip 3 feet wide was selected. Two views of it 

 from opposite sides are given in the plates, and its exact site is indicated 

 by the position of the sieve net in plate 4, and is occupied by the cage 

 in the foreground in plate 5. The collections were made July 10. The 

 water was about 3 inches deep at the bank, and descended somewhat 

 regularly toward the current side. Over nearly the whole of the area 

 there was an abundant growth of aquatics, most abundant among which 

 was a species of matted^ submerged Potamogeton, intermixed 

 with a variety of filamentous algae, and a little Nit ell a. The plants 

 which appeared above the water were water-cress, water-speedwell, and 

 a thin grass which I took to be a species of Leersia. There was 

 no bur reed growing in this plot. 



The following animals were taken from this plot. 



Vertebrates 

 I full-grown bullfrog, Ran a Catesbiana Sh^w, whose stomach 

 contained: 7 full grown snails, Physa heterostropha Say; i 

 dragonfly, $ Calopteryxmaculata Beauv.; i Crane fly (unde- 

 termined); I Scarabaeid beetle; 1 female winged carpenter ant; i Syrphus 

 fly (apparently one of the smaller members of the genus Syrphus); i 



