September, 1942 
reared), 4 nymphs. YELLOwsToNE NATIONAL 
Park, Soda Butte Creek: Aug. 2, 1940, T. H. 
Frison & T. H. Frison, Jr.. 1¢. Granp TETON 
NATIONAL Park, Beaver Creek and Cascade 
Canyon: Aug. 7-9, 1940, T. H. Frison & T. H. 
Frison, Jr. 56, 62 (1 reared), nymphs, 
exuviae. WILSON, Coal Creek: Aug. 12, 1940, 
YT. H. Frison & T. H. Frison, Jr., 1 nymph. 
I have studied a nymphal male in the 
collection of Cornell University collected 
Bomelictes Park Colo., Aug. 2, 1921,” 
which was determined as “P. expansa” by 
Claassen. It is probable that this is one 
of the specimens he describes and records, 
with erroneous date citation, from “Estes 
Park, Col., Aug. 4, 1921,” and states 
that “identification of this species was 
made possible by a study of the genitalia 
of both male and female nymphs.” ‘The 
genitalia of this male are well developed, 
but I cannot separate this specimen from 
similar well-developed nymphs which I am 
certain are modesta. It may be that ex- 
pansa is a synonym of modesta. 
It is possible that the nymph described, 
but not reared, by Claassen (1931) as 
Perla expansa Banks [now Diploperla ex- 
pansa (Banks) ] is of this species. This 
possibility is suggested because of the 
unidentate character of the lacinia. 
Diploperla pilata new species 
Mate. — General color yellowish to 
dark brown. Head and pronotum with 
dark and light areas forming a color pat- 
tern as in fig. 78. Legs, antennae and 
anal cerci yellowish brown. No gill rem- 
nants. 
Head wider through compound eyes 
than width of pronotum; lateral ocelli 
slightly more removed from one another 
than from anterior ocellus, distance be- 
tween them about twice the distance each 
is removed from inner edge of compound 
eye. 
Pronotum approximately quadrangular, 
somewhat broader than long, angles 
rounded, a distinct pattern of raised rugos- 
ities on surface each side of median longi- 
tudinal stripe, fig. 78. 
Legs with first and second tarsal seg- 
ments together about one-third as long as 
third, first tarsal segment slightly longer 
than second. 
Wings, fig. 78, essentially hyaline with 
venation dark brown; tip of wing with 
branches of radial sector slightly turned 
Frison: NortH AMERICAN PLECOPTERA 
305 
upwards; venation in general similar to 
that of wing figured for Dictyopterygella 
knowltont Frison (1937). 
Abdomen, fig. 78, with tenth tergite 
cleft for reception of narrow, elongate, 
supra-anal process, membranous on upper 
surface and sclerotized on lower surface, 
Hanked on each side by a slender, sclero- 
tized, lateral stylet (paragenital lobe) ; 
dorsal lobes on posterior margin of seg- 
ment bordering cleft shaped as in fig. 78, 
with some short, stout spines. Seventh 
sternite, fig. 78, with a broad lobe extend- 
ing slightly backwards, ninth sternite pro- 
duced backwards over tenth sternite but 
not upturned over tenth sternite. 
Length to tip of wings 16 mm.; length 
to tip of abdomen 13 mm. 
FEMALE.—Head, thorax, basal abdom- 
inal segments and appendages in general 
similar to those of male but slightly larger 
in size. Important differences are as fol- 
lows: eighth abdominal sternite, fig. 78, 
with subgenital plate greatly produced so 
that it covers most of the ninth sternite, 
hind margin of plate not indented, sides 
somewhat rounded. 
Holotype, male—Vedder Crossing pb Cs; 
May 10-26, 1936, W. E. Ricker. 
Allotype, female.—Same data as for holo- 
type. 
Paratypes. — British CoLUMBIA. — VEDDER 
CROSSING: Same data as for holotype, 34, 
179; Chilliwack River, April 24, 1937, S. 
Spencer, 1¢ ; May 9, 1937, Ricker & Spencer, 
73,39. Sumas RIVER: May 4-6, 1937, W. E. 
Ricker, 29. \Curtus LAKE: May 10-26, 1937, 
W. E. Ricker, 14, 19; Chilliwack River, 
May 8-22, 1938, S. Spencer, 29. 
OREGON.—DonGE Park, at confluence of 
Sandy and Bull Run rivers: June 22, 1933, 
R. Dimick, 19. Lacoms, Crabtree County: 
pune. 4, 119359Re Dimick. "1a. CuacKkamMAs 
County, Eagle Creek: June 20, 1935, S. G. 
Jewett, Jr, 89. Farmer’s River: June 20; 
1930, 1Q. Prospect: July 12, 1933, G. Hoppe, 
Oe ; 
W ASHINGTON.—GREEN 
2h t 933 eG elloppes lege 
NympH. — General color yellowish 
brown with darker areas on head, thorax 
and abdomen, as in fig. 79, Antennae, 
legs and anal cerci mostly yellowish. 
Head with three ocelli forming an al- 
most equilateral triangle, lateral ocelli 
about as far apart as each is distant from 
inner edge of compound eye; no occipital 
ridge; basal segments of mouthparts con- 
spicuously extending out laterally from 
the sides of head so that head appears 
much broader than thorax. 
RiviR Gorce: May 
