September, 1942 
ties and a longitudinal, median depressed 
line. Terminal abdominal tergites with 
groups or patches of small spinulae ar- 
ranged as in fig. 64 of Frison 1937. Gen- 
ital hooks or modified subanal lobes taper- 
ing to a point which is curved inwards 
at tip (fig. 64, Frison 1937). Subanal 
lobes show gill remnants. 
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 modified 
into a subgenital plate extending partly 
over ninth sternite and shaped as in fig. 
64 of Frison 1937. 
Holotype, female.—Petersburg, Ind.: reared 
from nymph from White River, June 11, 1936, 
T. H. Frison & C. O. Mohr. 
Allotype, male.—Same data as for holotype 
except reared June 9, 1936. 
Paratypes. — INDIANA.—PETERSBURG: Same 
data as for holotype and allotype with rearing 
dates as follows: June 3, 14; June 4, 30E8 
June 8, 145; June 9, On Sore June 10.2203 
mie 13, 39; June 15, 59; June Jain CAE SI 
July 6, 19. 
The female, instead of the male, has 
been selected as the holotype because it is 
easier to separate from other species of 
Acroneuria than is the male. The type 
series has been based upon Indiana speci- 
mens only because it is a reared series. 
Records for this species in the Illinois Nat- 
ural History Survey collection not recorded 
by me (1937) under the name evoluta are as 
follows. 
ILLINOIs.—OAKwoop: June 24, 1937, T. H. 
Frison, Jr.. 19. URBANA: July be VOD (Gab 
Riegel, 19. Eppyvitte, Lusk Creek: June 1, 
1940, B. D. Burks, 19. 
GEORGIA.—SUMMERVILLE: June 9, 1937 P. 
W. Fattig, 19. Rinccotp, Chickamauga Creek: 
June 14, 1930, P. W. Fattig, 16, 62. Daron: 
June 14, 1939, P. W. Fattig, 39. 
KANSAS.—LAWRENCE: June 30, 192 le PVE Ce 
12 (previously determined by Claassen as 
evoluta). 
OHI0.—ApDAMs County: June iil 930 sp eos 
Hine, 19. 
OKLAHOMA.— ARDMORE: June 8, 1939, Kaiser 
& Nailon, 12. Broken Bow: Junes 13521939: 
Kaiser & Nailon, 12, 19. 
TENNESSEE.—SPARTA: May 31, 1934, T. H. 
Frison, 19. 
Acroneuria filicis new species 
In my paper on the stoneflies of IIli- 
nois (19352), I commented at some length 
Tegarding the confusion in literature and 
determinations of species under the name 
Frison: NortH AMERICAN PLECOPTERA 
275 
pennsylvanica (Rambur). Ricker (1938) 
gives considerable information regarding 
specimens determined by Klapalek as penn- 
sylvanica, and one of the specimens he 
studied at Prague may be the missing type 
of pennsylvanica. Ricker comes to the con- 
clusion that pennsylvanica (Rambur 
1842) is identical with arenosa (Pictet 
1841) [not clara Klapalek (1917) = are- 
nosa sense of Klapalek (1909)]. Ac- 
cepting the synonymy indicated by Ricker, 
and I know of no valid reason to oppose 
his conclusion in this particular case, 
leaves an eastern North American species 
sometimes determined as pennsylvanica 
(Needham & Claassen 1922, 1925, at least 
in part) without a specific name. 
VE aA, Wie 
Vy. " 
Westra e 4 ay Ai 
rare A acts Ww 
Why até ae 
co’ TERMINAL ABDOMINAL 
STERNITES PLATE 
& Gite 
REMNANTS 
AND 
SuBANAL Hook 
coy Ml 
i f(t!) 
hw 
\Aa 
#\\\\ 
WN  S 
{ 
AY AWS 
? Gitt REMNANTS 
AND 
SUBANAL LOBE ' 
hf orn 
neta 
aH wh 
SS 
AR ae re 4] an | 
itl He i 
ee EY 
bah nN 
o' TERMINAL ABDOMINAL 
TERGITES 
9 HEAD AND 
PRONOTUM 
Fig. 41.—Acroneuria filicis. 
