PELTOPERLIDAE new family 
The genus Peltoperla has heretofore been placed in the fam- 
ily Perlidae. In a general way the adults are not greatly differ- 
ent from the adults of the other genera of the Perlidae, but 
the nymphs are so unique in structure and so unlike in habits 
from other genera that it seems best to place this genus in a 
separate family. 
The nymphs of Peltoperla are herbivorous while the nymphs 
of all the other genera of the Perlidae are carnivorous. 
The Peltoperlidae are readily recognized in the immature 
stages by the roach-like form of the nymphs; the large shield- 
like pro-; meso-, and metanotum; short abdomen; very wide 
legs; short cerci; and the short head bent under the body. The 
mouth parts are of the herbivorous type, and similar in struc- 
ture to the mouth parts of Pteronarcidae. 
The family is represented by a single genus Peltoperla which 
is distributed over the Eastern, Southern and Western States. 
Genus PELTOPERLA Needham 
The nymphs of this genus are readily recognized by their 
roach-like form. Body broad and flattened; the thorax consists 
of large brown chitinized plates which extend laterally over the 
side of the body; the head is curved under so as to be only part- 
ly visible from above; the abdomen is very short, with usually 
not more than five or six segments visible from above; on the un- 
derside, the thorax consists of three large plate-like shields rep- 
resenting the pro-, meso- and metasterna; the legs are broad and 
flattened. 
The wing pads are not clearly defined, but are present as con- 
tinuations of the meso- and metathoracie tergites; legs broad. 
and short; coxa very broad and posteriorly produced into a 
rounded lobe; femur with a deep groove on the inner margin, 
into which the tibia fits when the leg is folded; first and second 
tarsal segments short, subequal, and the two together less than 
half as long as the third segment. 
Gills, when present, occur as single fleshy filaments attached 
under the meso- and metasterna. According to Uéno, these fila- 
ments are attached to the coxae but in Peltoperla arcuata they 
are outgrowths of the meso- and metaplurae and originate near 
the base of the legs. 
The sexes are very similar in the nymphs but the females may 
