PLECOPTERA NYMPHS OF NORTH AMERICA 101 
tinguishable, typical of genus, with numerous cross-veins between 
medio-cubital longitudinal veins. Legs short, prothoracic legs 
shortest, metathoracic legs longest, femur and tibia of about 
equal length, femur much broader than tibia; tarsi three-seg- 
mented, second segment very small, third segment two or three 
times as long as first, and provided with two simple claws at 
apex; tibia at apex lower on side with two spines about one-third 
as long as the first tarsal segment; some short stout setae on 
ventral aspect of all segments. 
Abdomen appearing cylindrical, with lateral margins of seg- 
ments almost straight and not noticeably tapering towards the 
apex; first seven dorsal segments of about equal size, and slightly 
broader than long, eighth and ninth dorsal segments about twice 
as broad as long, tenth dorsal segment rounded behind, and from 
lateral aspect somewhat lobe-like and humped up at apex; ninth 
ventral segment with faint indication of lobe-like appendage 
visible through body, which is a large anal area somewhat pointed 
on posterior margin and longitudinally bisected by an incision 
for one-half of its length. Anal cerci, at least nineteen in one 
specimen; first few basal segments about as long as wide, suc- 
ceeding segments rapidly becoming much longer than wide, those 
towards apex much broader at apex than at base, and with a 
row of long stiff setae around each segment near apex. 
Nymphal Female. Similar in general to the male. Abdominal 
segments as a whole much broader than long, apical dorsal seg- 
ment broadly rounded behind and without hump-like lobe at apex, 
when viewed from lateral aspect. 
Harrisburg, Ill.; Herod, Il. 
Genus TAENIOPTERYX Pictet 
The nymphs of this genus are mostly blackish in color, in 
some instances yellowish brown, and in some species with a 
median, narrow, yellowish, longitudinal line, especially notice- 
able on the thorax; antennae and cereci very long and slender. 
The nymphs, when fully grown, measure from 10 to 14 mm. in 
body length. 
Head a little narrower than pronotum; three small ocelli, of 
which the posterior ones are at least twice as close to the eyes as 
to each other ; occiput marked with numerous granular markings. 
Pronotum somewhat widened posteriorly, angles rounded, and 
the sides slightly convex; surface somewhat rugulose; marginal 
sroove rather indistinct ; front wing pads slender and somewhat 
