September, 1942 
A recent study of the typic female of 
pallidula in the collection of the Museum 
of Comparative Zoology has revealed that, 
although faded and barely distinguishable, 
the type of pallidula does have the dorsal, 
longitudinal, dark stripe on the abdomen, 
as Needham & Claassen (1925) stated. 
Although females of Alloperla are not as 
satisfactory as males for purposes of spe- 
cific recognition, I have come to the con- 
clusion that pallidula and dubia are the 
same species and therefore the name dubia 
should fall in synonymy upon the basis of 
priority. 
This paper is also the proper place to 
correct another statement made by me in 
my 19355 paper involving dubia. At that 
time, I recorded that three specimens of 
fee Aue se etes: Park. Colo.’ material 
recorded by Needham & Claassen (1925) 
were without a dark dorsal stripe on the 
abdomen “and hence agree with the true 
pallidula Banks,” as I then accepted it. 
A restudy of these specimens reveals that 
this stripe was originally present but is 
now barely distinguishable because of fad- 
ing or bleaching in preservative. Recent- 
ly, Hoppe (1938) recorded both pallidula 
and dubia from Washington, but a check 
of her material named as these two species 
reveals that only one species—dubia—is 
involved. In other words, there is now 
no evidence that a western species exists 
which is structurally like pallidula but 
that differs in lacking the dark dorsal ab- 
dominal stripe. 
Frison: NortH AMERICAN PLECOPTERA 347 
Alloperla diversa Frison 
Alloperla diversa Frison (1935b, AOR R |. 
Original description, ¢, @. 
Alloperla nimbilis Hoppe (1938, p. 155) 
Original description, ¢. New synonymy. 
A study of the male type of nimbilis, 
through the courtesy of Professor Trevor 
Kincaid of the University of Washington, 
has revealed that it is practically identical 
with the male type of diversa, described 
from Oregon. The supra-anal process may 
differ slightly, but certainly no differences 
exist to warrant separate specific recogni- 
tion, in the absence of other characters. 
Hoppe did not record diversa from Wash- 
ington, and no mention is made in the 
original description of nimbilis of differ- 
ences from or similarities to diversa. 
Alloperla chloris Frison 
Alloperla chloris Frison (1934, p. 27). Orig- 
inal description, 6, @. 
Chloroperla milnei Ricker (1935, p. EOS )a 
Original description, $, 9. New synonymy. 
A restudy of a paratypic specimen of 
milnet in the Ilinois Natural History 
Survey collection and the cleared terminal 
abdominal segments of another paratypic 
specimen sent to me by Dr. W. E. Ricker 
on loan from the Royal Ontario Museum 
of Zoology, Toronto, Canada, has re- 
vealed that milnei is a synonym of chloris. 
Dr. Ricker states in a letter to-me that he 
concurs with my opinion regarding this 
synonymy. 
