480 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 113 
Material examined: Michigan, Curran, Yoder Creek at Route 72, 
May 21, 1936, 3 larvae (INHS). New Hampshire, Pinkham Notch, 
Cutler River, May 18, 1957, 5 larvae—Aug. 4, 1958, 1 larva—Aug. 24, 
1957, 1 larva; Mount Washington, Cutler River in Tuckermans 
Ravine, Aug. 4, 1958, 12 o'9 pupae—Aug. 24, 1957, 20 larvae. 
Remarks: The larvae were taken in a rushing mountain torrent 
about 3-5 yards wide. Adults were also collected on Mount Katahdin, 
Maine, beside a similar torrent. 
The larvae collected on Mount Washington show a steady increase 
in size from those collected in late August through the spring months 
to the few collected in early August. The adults emerge primarily 
in August. 
Ficure 7.—Rhyacophila acropedes: a, mandibles, dorsal aspect: b, anal proleg, lateral; c, 
head and pronotum, dorsal. 
Rhyacophila invaria group 
This is the largest group of species in the genus in eastern North 
America, containing 8 species. To date, larvae of envaria (Walker), 
nigrita Banks, viboz Milne, and shenandoahensis Flint have been 
reared. In addition, I can recognize three more larval forms in the 
material at my disposal. The known ranges indicate that these three 
are probably larvae of banksi Ross, carpentert Milne, and mycta Ross. 
