164 ILttinois NaturaAL History Survey BULLETIN 
low, as in interpunctatum and heterotarsale. 
Mate.—Length of body 7 mm., of fore 
wing 8 mm. Face below antennal sockets 
light yellow, a small, black mark on margin 
of frontal shelf ventral to each antennal 
socket; each antenna yellow, flagellum 
slightly grayed near base; area of face be- 
tween antennal sockets and ocelli deep yel- 
low: vertex Mars orange; eyes in life pale 
green. Pronotum yellow, black streak on 
either side; mesonotum amber-brown, with 
red-brown shading at posterior ends of outer 
parapsides and on lateral margins anterior 
to fore wing bases; mesoscutellum yellow in 
the center, Mars orange at margins, Mars 
orange shading also present on lateral mar- 
gins of mesonotum posterior to fore wing 
bases; pleura bright yellow, minute, a dark 
brown point on each middle and hind coxal 
suture; thoracic sternum bright yellow. 
Wings hyaline, stigmatic areas stained with 
brown, veins light yellow-brown, crossveins 
black, two crossveins below bulla connected 
by black dash; veins and crossveins of each 
hind wing pale yellow, but crossveins and in- 
tercalaries at outer margin black; fore fe- 
mur deep yellow, median and apical, dark 
brown crossbands present, tibia pale yellow, 
apex black, tarsus white, apexes of segments 
slightly darkened, first segment three-fifths 
as long as second segment; middle and hind 
legs white, each femur with a faint, dark 
brown shading in middle and a well-marked, 
brown band at apex. Abdomen white, pos- 
terior margin of each tergite 1-7 with Mars 
orange crossband; spiracular dots absent; 
apical three tergites yellow-orange, with 
overlying Mars orange shading; genitalia, 
fig. 336, white ; caudal filaments white, artic- 
ulations not darkened. 
Holotype, male. — Oakwood, Illinois, 
June 25, 1948, B. D. Burks. Specimen dry, 
on pin. 
Paratypes.—Same data as for holotype, 
24. Specimens dry, on pins; genitalia on 
microscope slide. 
5. Stenonema minnetonka Daggy 
Stenonema minnetonka Daggy (1945:376). 
Mave.—Length of body 9-10 mm., of fore 
wing 10-11 mm. Head yellow, a black mark 
on face ventral to each antennal base; vertex 
shaded with orange-brown on meson and at 
posterior margin; antennal scape and pedicel 
Vol. 26, Art. 1 
yellow, flagellum gray-tan at base, hyaline 
at tip. Mesonotum brown, scutellum yellow; 
semimembranous area anterior to base of 
fore wing shaded with light orange-brown, 
pleuron yellow, sternum yellow; fore leg 
deep yellow, apex of tibia and apexes of all 
tarsal segments black, first tarsal segment 
one-half as long as second; middle and hind 
legs yellow, tarsi shaded with gray-brown; 
middle and apex of each femur usually 
shaded with dark brown, middle band on 
hind femur sometimes obsolescent; wings 
hyaline, stigmatic area of fore wing stained 
with brown, veins yellow-brown, crossveins 
very dark brown or black; hind wing with 
all veins and crossveins yellow, outer margin 
dark brown. Abdomen yellow, black cross- 
band at posterior margin of each tergite 
1-8 with a black crossline; spiracular marks 
present; posterior half of tergite 8 and all 
of tergites 9 and 10 shaded with orange- 
brown; genitalia, fig. 335, yellow; caudal 
filaments gray-yellow, articulations brown. 
Known from Illinois and Minnesota. 
Illinois Records. — BENTOoN: at light, 
June 10, 1946, H. H. Ross, 2 6. FREEPORT: 
June 10-11, 1948, Burks, Stannard, & Smith, 
14. Quincy: July 6, 1939, Mohr & Riegel, 
1¢. Rockrorp: May 22, 1941, Ross & 
Burks, 1¢. SHAWNEETOWN: July 14, 1948, 
Mills & Ross, 1¢. 
6. Stenonema canadense (Walker) 
Baetis canadensis Walker (1853:569). 
Stenonema interpunctatum canadense 
(Walker). Spieth (1947:107). 
Stenonema conjunctum Traver (1935a:309). 
Stenonema ohioense Traver (1935a:322). 
Stenonema proximum Traver (1935a:325). 
Spieth (1947:109) considers that proxi- 
mum and conjunctum are synonyms of the 
form that he designates as interpunctatum 
frontale (Banks). 
In the Museum of Comparative Zoology, 
the specimens determined as interpunctata 
(Say) by Walsh are clearly of the species 
we now are calling canadense (Walker). 
Walsh’s redescription (1862:374) of inter- 
punctata (Say) also obviously fits the pres- 
ent-day concept of canadense, and, as Spieth 
has shown (1940:333), the current concept 
of canadense is in agreement with Walker’s 
type. The type of interpunctata is lost, but — 
the original description of this species more | 
nearly matches the species at present called — 
