Populations of all stages of three species of Hydropsychidae, Hydropsyche simulans, Cheumatopsyche campyla, and Cheumatopsyche lasia were sampled fro September, 1971, to August, 1972, on the Brazos River in Palo Pinto County, Texas. Supplemental observations relating to emergence, mating and oviposition, and larvae food habits were continued to July, 1973. The purpose of this study was to elucidate the life cycles and ecology of this Hydropsychidae complex.