288 
Arcynopteryx lineata Smith (1917, p. 476). 
Original description, 2. New synonymy. 
Perlodes margarita Alexander (1936, p. 26). 
Original description, ¢@. New synonymy. 
Apparently every time a specimen of 
this species has fallen into a collector’s 
hand it eventually has formed the basis for 
a description of a new species. he syn- 
onymy I have indicated above is based 
upon a study of the holotypic female of 
lineata (C. U. No., 1,138) and the typic 
Fig. 55.— 
Perlodes 
minor. 
QSUBGENITAL PLATE 
female of slossonae (M.C.Z. No. 11,308). 
Certainly both of these are identical as to 
species. Fig. 55 is an illustration of the 
subgenital plate of the holotypic female 
described by Smith (1917) as lineata. 
Male and female specimens of minor 
determined by Klapalek are in the collec- 
tion of the Museum of Comparative Zo- 
ology. When these were compared with 
specimens of Perlodes from Mount Wash- 
ington, N. H., previously determined as 
lineata, and with the type of slossonae, no 
tangible differences could be found. Spe- 
cies of stoneflies have a much more general 
distribution within certain limits than lit- 
erature records indicate. Although I have 
not examined the type of margarita I feel 
quite certain that it is the male of the spe- 
cies Banks described as s/ossonae—they 
even came from the same mountain— 
which in turn is the same species as lineata 
from nearby New York. On the highest 
mountains in the East are a few species of 
stoneflies found at lower levels farther 
north. 
Klapalek’s minor is a species of Perlodes 
having a pair of gill remnants in the adult 
only on the submentum. In western North 
America there is another species of Per- 
lodes named americana (Klapalek) closely 
related on the basis of gills to minor but 
with a distinctive subgenital plate in the 
female and with different genitalia in the 
male. P. ignota (Smith), described 
(1917) without locality data, is evidently 
another synonym of minor, but the type 
could not be found when my studies of the 
Perlodes types were made. 
I_Linotis NATURAL History SURVEY BULLETIN 
V ol. 22, Art 
Perlodes aurea (Smith) 
Arcynopteryx aurea Smith (1917, p. 477). 
Original description, @. ; 
Arcynopteryx vagans Smith (1917, p. 478). 
Original description, ¢. New synonymy. 
Arcynopteryx aurea was described from 
a single female (C.U. No. 1,141) from 
“San Diego, Calif., April 23, 1879,” and 
vagans from a single male (C.U. No, 
1,139) from ‘“‘California.” 
I have studied the types of both aurea 
and vagans and as a result have come to 
the conclusion that the specimen described 
as vagans is the male of aurea, the name 
aurea having page priority. My reasons 
are as follows: Males and females agree- 
ing with these two sexes occupy the same 
general territory, the opposite sex of each 
has not been previously located, and 
morphologically both are unique among 
North American species of stoneflies in 
having five pairs of gill remnants, fig. 56. 
h BS if ‘ 
raw 
Ny * ye 
SS 
re 
Ss 
ADULT HEAD 
AND PRONOTUM 
Q SUBGENITAL PLATE 
Fig. 56.— 
Perlodes aurea: 
A, female holotype 
from California; 
B, female specimen 
from Oregon. 
An illustration of the subgenital plate 
of the female holotype of aurea is present- 
ed in fig. 564. Fig. 56B is an illustration 
of the subgenital plate of a female | con- 
sider to be aurea from Oregon. The head 
and pronotum of aurea, as observed in an 
Oregon specimen, has a pattern as in Ng. 
56. Although Needham & Claassen 
(1925) mentioned the five pairs of gills in 
