September, 1942 
1935, R. Dimick, 14 ; Molalla River, June 13, 
1938, S. G. Jewett, Jr., 14 ; Willamette River, 
May 26, 1938, C. Jensen, 19. 
British CoLUMBIA.—CuLTUs LAKE: lower 
Sweltzer Creek, May 12, 1937, W. E. Ricker, 
53,22; Sweltzer Creek, June 4, 1937, Ricker, 
36, 12; Chilliwack River, April 24, 1938, 
Ricker & Spencer, 24, 29; Chilliwack River, 
May 22, 1938, S. Spencer, 34. VEDDER CRoss- 
ING: May 5, 1937, W. E. Ricker, 19 ; May 19, 
L7o7 WV. E~ Ricker, 3:3. 
Isoperla pinta Frison 
Isoperla pinta Frison (1937, p. 92). Orig- 
inal description, ¢, 9, nymph, 
Isoperla tokula Hoppe (1938, p. 157). Orig- 
inal description, 6, 9. New synonymy. 
Through the kindness of Professor 
Trevor Kincaid of the University of 
Washington, I have had the privilege of 
studying the holotype, allotype and para- 
types of tokula. This is the same species 
as pinta, and hence tokula must be placed 
in the synonymy of pinta on the basis of 
date priority. 
Isoperla fulva Claassen 
Isoperla fulva Claassen 
Original description, ¢, 9. 
Isoperla chrysannula Hoppe (1938, p. 156). 
Original description, ¢. New synonymy. 
Isoperla cascadensis Hoppe (1938, p. 158). 
Original description, 6, 9. New synonymy. 
A study of the types of fulva, chrysan- 
nula and cascadensis has convinced me 
that only one species of Isoperla is in- 
volved, which will take the name of fulva 
on the basis of date priority. The types 
of fulva have been studied through the 
courtesy of Dr. Henry Dietrich of Cornell 
University, and the types of chrysannula 
and cascadensis through the courtesy of 
Professor Trevor Kincaid of the Uni- 
versity of Washington. 
The typic specimen of chrysannula dif- 
fers from the types of fulva and cascaden- 
sis in that the costal vein of the forewing 
Is not connected with the radial vein. In 
view of agreement in all other respects, 
the frequency of variation in details of 
Wing venation in general, and variation 
existing within the same species, it is my 
opinion that the absence of part of the tip 
of the costal vein in chrysannula is an 
instance of variation. 
The description by Hoppe of cascaden- 
sis as a new species can be explained by 
the probability that Claassen’s description 
of fulva was overlooked. This probability 
(19374, p. 80). 
Frison: NortH AMERICAN PLECOPTERA 
By 
is indicated by the lack of any citation of 
this particular article in the bibliography 
given by Hoppe and by the lack of recog- 
nition of fulva from Washington, where 
it occurs. Claassen’s paper appeared sev- 
eral months before Hoppe’s paper was 
published and therefore has priority. 
A study of the types of cascadensis has 
failed to reveal any characters which defi- 
nitely separate the species from fulva. The 
lobe on the posterior margin of the eighth 
abdominal sternite is subject to variation 
in size, depending upon age of specimen 
and other factors. Hoppe’s figures of the 
male eighth abdominal sternites of chrys- 
annula and cascadensis would seem to indi- 
cate a wide difference in respect to size 
of the lobe on the posterior margin of this 
sternite, but such a great difference does 
not exist because of reasons just men- 
tioned. 
CHLOROPERLIDAE 
Considerable confusion has resulted in 
stonefly literature, both in Europe and 
North America, because of the erroneous 
interpretation of the genotype of Chloro- 
perla Newman (1836). Banks (1906d) 
was first to point out that Isopteryx Pic- 
tet (1841) was synonymous with Chloro- 
perla Newman (1836) and to recognize 
that the Chloroperla of Pictet contained 
two previously unnamed genera for which 
he proposed the names of 4/loperla and 
Isoperla. Kimmins (1936), in a recent 
study of the British species of Chloroperla, 
has confirmed the work of Banks in regard 
to synonymizing Isopieryx with Chloro- 
perla and in proposing the new generic 
names of Alloperla and Isoperla. In addi- 
tion, Kimmins has shown that the geno- 
type of Chloroperla was established by 
Westwood (1840) as C. tripunctata 
(Scopoli) [= C. lutea (Latreille) ]. 
Another source of trouble in North 
American literature has been an erroneous 
conception of the species described from 
Georgia by Newman (1839) under the 
name of Chloroperla cydippe. Ricker’s 
(1938) comments and drawings, and ad- 
ditional information furnished to me 
through the kindness of D. E. Kimmins 
of the British Museum, prove that the 
typic specimens of cydippe are not of 
the species assigned to this name by Hagen 
(1861), Needham & Claassen (1925) 
