This is the second paper in a series on the emergence patterns of aquatic insects from a sandstone‐shale first‐order stream of northwestern Pennsylvania. Fifteen species, with 6,708 specimens, in six families were collected from the Sixmile Creek site over five years. Adults occurred from March through August in 1977–79, in January 1980 and September 1981. Peak months of emergence in terms of total collection were May, withSweltsa onkos(Ricker) andAmphinemura nigritta(Provancher) predominant, and July withLeuctra tenuis(Pictet) predominant.