338 Iutinois Naturat History SURVEY BULLETIN 
and others, and that cydippe belongs to 
the genus dlloperla. 
The establishment of the fact that 
cydippe (Newman) belongs to the genus 
Alloperla makes brevis (Banks 1895) an 
available name for the species erroneously 
called cydippe by Hagen, Needham & 
Claassen and other north American writ- 
ereusince then» “Lherpossibilitysorssuch: 4 
usage I suggested in 1937, but no definite 
stand was taken in regard to this use of 
names at that time because the status of 
cydippe had not been definitely deter- 
mined. Furthermore, the name of Hasta- 
perla Ricker (1935a) now becomes avail- 
able as the generic name for brevis 
(Banks), since the genotype of Hasta- 
perla is an outright synonym of brevis 
(Frison 1937); and Chloroperla, on the 
basis of its genotype, must be associated 
with another group of closely related spe- 
cies. Along with brevis, the species orpha 
(Frison 1937) should now be placed in 
Hastaperla. 
Ricker (1938) suggested the possibility 
that Alloperla Banks is synonymous with 
Chloroperla Newman. Basing my _ con- 
clusions upon comparative studies of true 
specimens of Chloroperla from Europe 
named by Kimmins with North American 
specimens of Alloperla, 1 find that Allo- 
perla should be accepted as a valid generic 
name for certain North American species, 
and probably some Asiatic species, now 
eoing by this name. My reasons for the 
recognition of Alloperla Banks as generi- 
cally distinct from Chloroperla Newman 
are as follows: (1) in Chloroperla the 
hooked supra-anal process (see Kimmins 
1936) of the male is not mounted on a 
large membranous base deeply recessed 
in the broadly cleft tenth abdominal ter- 
gite as is the case in dlloperla, and (2) 
the second anal vein of the forewing in 
Chloroperla does not appear branched as 
a result of fusion with base of third anal 
vein as is the case in Alloperla. 
There is, however, a North American 
species of Chloroperlidae, recognized and 
described for the first time in succeeding 
pages of this article, which seems best 
placed generically in the genus Chloro- 
perla Newman, as defined and used by 
Kimmins (1936). It is true that the male 
of this new species differs from the geno- 
type of Chloroperla [tripunctata (Sco- 
poli) | by the presence of a small projec- 
V ol. 22, Arte 
tion on the seventh abdominal sternite, 
but its general habitus, small size, color 
pattern, wing shape and venation, and 
structure of terminal dorsal abdominal 
segments otherwise place it with or very 
near to Chloroperla (s.s.). 
What has just been stated, when prac- 
tically interpreted, results as follows: (1) 
Isoperla Banks is the valid generic name 
for a group of species [genotype bzlineata 
(Say) | in North American literature now 
going under this name, and also for certain 
Eurasian species, many of which have 
been going under the generic name of 
Chloroperla (1.e. Chloroperla in the sense 
of Despax 1936); (2) Chloroperla is a 
valid generic name for certain European, 
and possibly Asiatic, species which have 
gone under the names of Chloroperla and 
Isopteryx, and for a new species from east- 
ern North America described in this 
paper; (3) Hastaperla Ricker (1935), 
as I suggested in 1937, becomes the generic 
name for two North American species, 
orpha (Frison) and brevis (Banks), the 
latter misidentified in most North Ameri- 
can literature under the name cydippe 
(Newman) ; and (4) Alloperla is a valid 
generic name for certain North American 
species, and possibly some Asiatic species, 
now going by this name. 
Admittedly, Chloroperla, Hastaperla 
and Alloperla are closely related, but from 
the standpoint of comparing the world 
fauna, there are advantages at present in 
considering them as distinct genera, at 
least until the Chloroperlidae of the world 
are better known. Kathroperla and Para- 
perla, belonging to this same family, are 
much more distantly related. 
The removal of Isoperla from the 
Chloroperlidae, as done elsewhere in this 
paper, and the recognition in North Amer- 
ica of the genus Chloroperla as defined 
by Kimmins (1936), warrants a new key 
for the separation of the genera of Chloro- 
perlidae as follows. 
KEY TO ADULTS, NORTH AMERICAN 
GENERA OF CHLOROPERLIDAE 
1. Hindwing without a distinct folded anal 
lobe, fig. 115... ..0 02a Hastaperla 
Hindwing with a distinct folded anal 
lobe, figs. 116-118........... 7 33ee 2 
2. Head much longer than pronotum, com- 
pound eyes situated far forward on 
sides of head so that the distance be- 
tween each compound eye and front 
