March, 1915.] LlOYD : NOTES ON AsTENOPHYLAX ARGUS. 57 



NOTES ON ASTENOPHYLAX ARGUS HARRIS. 

 (TRICHOPTERA).i 



By J. T. Lloyd, 

 Ithaca, N. Y. 



During the hot days of August, when the streams of our fields and 

 gorges are low and warm, if one goes to the alder-swamps to the 

 north or south of Ithaca he will find clear, cool streams maintaining 

 an abundant flow of water. In winter when our deeply frozen nearby 

 streams do not break the snow-cover of adjacent fields, except where 

 narrow dark lines carpeted with anchor ice mark the course of the 

 swiftest riffles, the open waters of the swamp streams show as narrow 

 lines of black contrasted to the snow cover of surrounding thick- 

 ets. Onl}^ in the severest weather a film of ice forms across their 

 most quiet regions and in protected bays along their banks. And when 

 in spring, the snow melts and the freshets come, the surface-fed 

 streams quickly rise to many times their normal volume, their muddy 

 waters overflowing low banks and rushing in deep torrents through 

 gorges, carrying sand and pebbles and grinding with large boulders, 

 the swamp-streams flow quietly on, their clear waters hardly above 

 their August levels and their bottoms of twigs and fragments of 

 vegetable-matter undisturbed by torrents. 



Springfed streams are these, whose water pours from the ground 

 at the foot of nearby hills, or seeps from beds of sphagnum in neigh- 

 boring bogs. Always clear and but slightly affected by changes of 

 temperature or precipitation that completely alter conditions in lakes 

 and rivers, their waters are as nearly uniform as is possil)le in our 

 changing climate. 



As might be expected under these uniform conditions, their inhabi- 

 tants, unlike most creatures of more changeable streams, alter their 

 habits but little during the seasons. In winter, as in summer, they 

 crawl actively over the bottom, feeding and carrying on their usual 

 activities. In both seasons the stomachs of the species we have ex- 

 amined have been equally gorged. 



1 Contribution from the Limnological Laboratory of the Department of 

 Entomology in Cornell University. 



