May, 1953 
as one compound eye. Thorax brown on 
dorsum and pleura, sternum tan. Legs yel- 
low, each femur with a black streak at 
apex, fore tibia and fore tarsus shaded with 
brown; first fore tarsal segment one-fourth 
as long as second segment; wings hyaline, 
veins and all crossveins but those posterior 
to Cu, in fore wing brown, with brown 
clouds surrounding crossveins in costal and 
subcostal interspaces as well as those pos- 
terior to bulla; stigmatic area stained with 
brown; veins and crossveins of hind wing 
almost or quite colorless. Abdomen white, 
each tergite tinged with tan in posterior 
half; a black crossline at posterior margin 
of each tergite; genitalia, fig. 377, light tan 
to white; caudal filaments white. 
NympH.—Unknown. 
This species is known from Ohio and 
Ontario. 
16. Heptagenia juno McDunnough 
Heptagenia juno McDunnough (1924):121). 
Mace.—Length of body 5.5-6.5 mm., of 
fore wing 6.5-7.5 mm. Head white, with a 
narrow, brown crossline at base of frontal 
shelf and at posterior margin of vertex; 
compound eyes separated on meson by a 
space as wide as one eye. Thorax cream 
colored, a longitudinal, black line on each 
pleuron above coxae, and a vague, dark 
streak at bases of each pair of wings; legs 
light yellow, each femur with a dark streak 
at apex, first fore tarsal segment one-fourth 
as long as second; wings hyaline, all veins 
except anterior ones of fore wing hyaline, 
crossveins of fore wing anterior to Cu, 
brown, others hyaline, crossveins in costal 
and subcostal interspaces of fore wing sur- 
rounded by brown clouds. Abdomen white, 
a black line at posterior margin of each 
tergite 1-7; apical tergites each vaguely 
darkened in mesal area with brown; venter 
white; genitalia, fig. 378, white; caudal fila- 
ments white. 
FEMALE.—Length of body 5 mm., of fore 
wing 6.5 mm. Coloration similar to that of 
male, but light yellow of thorax becoming 
white or almost white; transverse, black 
marks at posterior margins of abdominal 
tergites faint or wanting, terminal three 
tergites not darkened; posterior margin of 
terminal abdominal sternite produced on 
meson as an obscure, blunt point; caudal 
filaments white. 
Burks: THe Mayr ies oF ILtInots 193 
NympH.—Length of body 6 mm. Head 
dark gray-brown, slightly wider than pro- 
notum, three white spots on margin just 
anterior to either compound eye. Thorax 
dark grayish-brown, with numerous white 
spots, each tarsal claw with a small, basal 
tooth and four or five ventral denticles. Ab- 
domen dark gray-brown, with white spots, 
tergite 1 mostly white, tergites 7 and 8 with 
a coalescing, median, white blotch, tergite 
9 white at anterior margin, dark posteriorly ; 
sternites 8 and 9 each with a transverse, 
dark brown mark on meson of anterior mar- 
gin; caudal filaments white, articulations 
brown. 
This species is known from Kentucky, 
New York, Pennsylvania, Quebec, and Ten- 
nessee. 
17. Heptagenia minerva McDunnough 
Heptagenia minerva McDunnough 
(1924:121). 
Mare.—Length of body 6 mm., of fore 
wing 7 mm. Head yellow, with a black, 
transverse line at base of frontal shelf and 
at posterior margin of vertex; compound 
eyes separated on meson by a space as wide 
as one eye. Thorax cream colored, with a 
median, brown streak on anterior third of 
mesonotum and a very dark brown spot on 
either side of base of mesoscutellum; a longi- 
tudinal, black line on each pleuron above 
coxae. Legs yellow, fore femur with a me- 
dian, reddish spot and an apical, black 
streak; wings hyaline, veins of fore wing 
brown, crossveins darker brown, crossveins 
of costal and subcostal interspaces sur- 
rounded by brown clouds, as are those pos- 
terior to bulla; outer fork with brown cloud 
at base. Abdomen faint yellow or white, 
each of tergites 1-7 with a transverse, black 
line at posterior margin and a pair of sub- 
lateral, elongate, brown triangles; apical 
three tergites shaded with red-brown; ven- 
ter, genitalia, fig. 379, and caudal filaments 
white. 
FEMALE.—Length of body 7 mm., of fore 
wing 8 mm. Coloration similar to that of 
male, but generally lighter, with light yel- 
low of thorax becoming white; dark shading 
of abdominal tergites much reduced, ter- 
minal tergites white. 
NympH.—Unknown. 
The species is known from Maryland and 
Ontario. 
