152 THOMAS SAY FOUNDATION 
PLATE 14 
FIGURES 186-187 
186 Peltoperla arcuata Ndm. 
Dorsal view of nymph. 
187 Peltoperla arcuata Ndm. 
Ventral view of nymph. 
Roach-like; brown; head bent under; pro-, meso- and metanotum 
very wide; pro-, meso-, and metasterna very large; gills composed 
of single filaments; cerci very short. ; 
