306 ILLtno1s NATURAL History SURVEY BULLETIN 
Labium, maxillae and mandibles as in 
fig. 78. 
A small, nipple-like projection at each 
outer posterior corner of the submentum 
suggestive of an atrophied submental gill, 
fig. 78. No true submental gill. 
NYMPHAL 
MANDIBLES 
NyYMPHAL 
LABIUM 
NyMPHAL 
MAXILLA 
3 ABDOMINAL 
STERNITES 
o& TERMINAL 
ABDOMINAL 
TERGITES 
9 HEAD AND 
PRONOTUM 
9 SUBGENITAL PLATE 
V ol. 22, Arta 
Pronotum much broader than long; 
outer margins darkly outlined and central 
area mostly light colored, raised rugosities 
faint. 
Abdominal tergites mostly yellowish 
brown with narrow, dark, transverse 
stripes prominent on anterior margins and 
weaker on posterior margins, fig. 79; ter- 
gites, except for posterior margins, mostly 
devoid of short, stout setae. Cerci long, 
many segmented, segments progressively 
longer from base to apex; a longitudinal 
row of long, fine setae on dorsal surface 
in addition to smaller spinelike ones en- 
circling apex of each segment. 
LEFT WINGS 
RIGHT WINGS 
LATERAL VIEW DORSAL VIEW) 
Nil “Wm, 
SupRA-ANAL PROCESS 
Fig. 78.—Diploperla pilata. 
