May, 1953 
notum dull, light brown, pleura and sternum 
yellow. Legs yellow, apex of each fore 
femur and fore tibia, and fore tarsus shaded 
with dull brown, first fore tarsal segment 
one-third as long as second; wings hyaline, 
veins and crossveins colorless. Abdominal 
tergites shaded with orange- or red-brown, 
this shading more intense at posterior mar- 
gins of tergites; genitalia, fig. 371, yellow, 
apical two forceps segments slightly smoky; 
caudal filaments white or faint yellow, with 
basal articulations red-brown. 
FremMaALe.—Length of body 4-5 mm., of 
fore wing 6-7 mm. Head tan, stained with 
orange; legs, thorax, and abdomen colored 
as in male; posterior margin of terminal 
abdominal sternite produced on meson, 
truncate; caudal filaments white. 
NympH.—Unknown. 
This species is known from Illinois, In- 
diana, Manitoba, Missouri, Ohio, and Wis- 
consin. 
Illinois Records.—Di1xon: June 
27, 1935,26,22 ; at light, June 25, 1947, B. 
D. Burks, 1¢. LAkE GLENDALE: May 16, 
1947, B. D. Burks, 1 ¢. Oakwoop: June 6, 
25) 12 H: Frison, 23 ; June 9, 1926, T. 
H. Frison, 62 ; June 23, 1948, B. D. Burks, 
44; June 24, 1948, Mills & Ross, 16. 
Orecon: July 18, 1927, Frison & Glasgow, 
1g. RicHMoND: June 20, 1938, B. D. 
Burks, 146; Aug. 15, 1938, Ross & Burks, 
36,592. RockrorD: June 29, 1938, B. D. 
Burks, 1¢. SoutH Be oir: July 2, 1931, 
Frison, Betten, & Ross, 1 ¢. St. CHARLES: 
at light, July 8, 1948, Ross & Burks, 16, 
19. Urpana: at light, July 5, 1907, 14; 
July 8, 1931, H. H. Ross, 1 ¢. WaAuKEGAN: 
Aug. 15, 1938, Ross & Burks, 5¢. 
10. Heptagenia lucidipennis (Clemens) 
Ecdyurus lucidipennis Clemens (1913:329). 
Mare.—Length of body 6 mm., of fore 
wing 7 mm. Head with face yellow, shaded 
with brown, vertex dark brown or red- 
brown; compound eyes contiguous on meson. 
Thoracic notum brown, pleura and sternum 
yellow. Legs yellow, fore femur shaded with 
brown, first fore tarsal segment one-fourth 
as long as second; wings hyaline, costa and 
subcosta of fore wing slightly grayed, other 
longitudinal veins and all crossveins color- 
less. Dorsum of abdomen dark brown, 
venter yellow; each basal tergite with dark- 
shaded area vaguely interrupted by a 
Burks: THE Mayr ties oF ILLINOIS 189 
lighter, longitudinal, median line and a pair 
of obscure, submedian streaks; genitalia, 
fig. 372, yellow; caudal filaments light yel- 
low, almost white, with faint, gray shading 
in basal halves. 
FEMALE.—Length of body 6 mm., of fore 
wing 8 mm. Color pattern very similar to 
that of male, but slightly lighter, the yellow 
areas almost white and the brown arxeas tan 
or reddish; caudal filaments white. 
NympH.—Length of body 7-8 mm. Head 
as wide as pronotum, dark brown, with 
numerous small, white spots. Thorax pre- 
dominantly white, with numerous dark 
brown spots on dorsum; each tarsal claw 
with large basal tooth and several ventral 
denticles. Abdominal dorsum predominantly 
brown, each tergite typically white along 
posterior margin, two submedian and two 
anterolateral, white spots in brown area 
near anterior margin; gills of anterior seg- 
ments each with ventral, filamentous tuft 
well developed; pair of gills on segment 6, 
each with filamentous tuft small and re- 
duced; pair on segment 7 without ventral, 
filamentous tufts; caudal filaments white, 
unmarked. 
Known from New York, Ohio, and On- 
tario. 
ll. Heptagenia perfida McDunnough 
Heptagenia perfida McDunnough (1927):301). 
Mave.—Length of body 5.5-6.5 mm., of 
fore wing 6.5-7.5 mm. Head yellow, with 
red-orange shading; compound eyes bluish 
gray, contiguous on the meson. Thoracic 
notum chestnut brown; pleura tan, paling 
to yellow ventrally, sternum yellow. Legs 
yellow, apical half of fore femur red-brown, 
fore tibia and fore tarsus shaded with faint 
gray; wings hyaline, veins and crossveins 
colorless except that costa and subcosta of 
fore wing sometimes show faint, yellow 
staining. Abdominal tergites a deep, rich 
brown, with anteromesal area of tergites 
2-8 yellow-brown, a longitudinal, median, 
yellow line and a pair of submedian, yellow 
streaks often visible within this yellow- 
brown area; venter yellow; genitalia, fig. 
373, yellow, apical margin of forceps base 
with a pair of sublateral, prominent, setose 
projections; caudal filaments light yellow, 
basal articulations brown. 
FEMALE.—Length of body 5.5-6.5 mm., 
of fore wing 7.5-8.5 mm. Head yellow, with 
