Article beginning on page 13.
Psyche 7:13, 1894.

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January 1894.1
PSYCHE.
WING-LENGTH IN SOME NEW ENGLAND ACR1DIQAE.-I. BY ALBERT P. MORSE, WKLLESLEY, MASS.
The title in full of this paper may be
stated as "Length of wings as an evi-
dence of specific distinctness and its value as a diagnostic character in reference to some New England Acrididae." In
using the term length of wing the length of the wing-covers or tegmina is in many instances included.
It was formerly the custom among
writers on this family to base specific
distinctness more or les largely 011 a
difference in the length ofwing presented by some closely allied forms, and to give keys for the detei mination of species in which this was used as a diagnostic
chaiactei-.*
My experience with New England
forms has led me to conclude that this
character of wing-length as found in
some of these is extremely unreliable,
and that the description of a new species founded wholly or largely on this charac- ter should be received with great caution. As an instance of specific variability
on this point let me cite the case of
Ofomala bruchyptera Scudd. This
locust, a well-known and widely-dis-
tsibuted species, possesses ordinarily
*A still more unsatisfactory practice was that of corn. paring the wing-length to the abdomen, thus : "Tip of
ivings passin~abdomen." The abdomen of the female locust is so variable in length, owing to size and num- ber of eggs, and extension due to oviposition, that it seems strange that any one should have used this rela- tion when one of equal practical value not subject to variation exists, viz: comparison with the hind femora, wing-covers extending on the hind
femora in the male to about one-half the distance to the tip,
in the female to
about one-fourth or one-third the dis-
tance to the tip, the wings in both sexes being nearly or quite aborted. In July,
1892, I had the good fortune to capture
a female similar in all respects to the
ordinary form but having the tegmina
extending to the end of the femora and
the wings fully developed. Could it
be another species ? Further search
soon resulted in the capture of a nor-
mal male brachyptera and left little
doubt in my mind that here was a case
of reversion to the earlier long-winged
form of female. Search in another
locality several miles distant resulted in the capture of over fifty specimens
among which were four long-winged
females and two long-winged males, I
have since obtained another long-
winged male from a neighboring town
and Mr. Scudder has one in his collec-
tion from Iowa.
Turning to the genus ChloeaZtis, -
or as it is also known, Chrysochraon, -
we find three forms described as occur-
ring in New England. In one of these,
C. conspersa, the female possesses
abortive wings and the tegmina rarely
reach half-way to end of femora. Both
wings and tegmina are somewhat
more developed in the male but not
enough to serve as organs of flight. I




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14 PSYCHE. [January 1894-
have never seen any long-winged speci-
mens in New England but Mr. W. S.
Blatcldey states (Can. ent., 1891, 76)
that he has taken a female in Indiana.
C. covzsjersa is quite uniform in color- ing, being invariably brown or straw-
color, never green, while the other two
forms or so-called species present an
interesting case of dimorphism in color, specimens of both sexes being partly or
wholly either brown or green ; most
commonly, the females are wholly green
or brown and the males green above with
brown sides, and mating with females
of either color.
Ordinarily the wings and tegmina are
of about equal length, reaching, in the
male, about half-way down the femora,
and in the female rather less, in the form called C. viridis, and in the other form, C. functulata, reaching to the end of
fem.ora. Specimens occur having wings
and tegmina of an intermediate length,
and short-winged males mate freely with
long-winged females of either color ;
long-winged males appear to be ex-
tremely scarce, but all the other forms
are common, the long-winged much less
so than the short-winged.
No other characters of more than
individual importance are presented by
these two forms to indicate them as dis- tinct, The two are found associated in
time and place, and mated, whence I
conclude that without a doubt the long-
winged, less common form, is the
ancestral form which is giving place to
the other.
Continuing in another genus of the
Fryxal inae,-Stenobotfirus,- we meet
two forms, quite variably colored and
presenting a marked contrast in length
of tegmina and wings, which have long
been considered to belong to one spe-
cies, 5'. curti'pennis and S. longifennis. These are about equally plentiful. The
long-winged form frequently makes use
of its wings in locomotion while the
other is obliged to resort to a more
prosaic mode of progression.
Take next the two species S. aepalis
and S. maculipennis. Here structural
differences in the vertex and, pronoturn are usually, but not always, accompa-
nied by a difference in length of wing
serving to distinguish the two species.
Owing to the fact that long-winged indi- viduals occur in the short-winged species and to the wide variation in color pre-
sented by both species they have been
much confused and misunderstood by
various authors.
Lembert of Yosemite, Cal., and remarked
PROCEEDINGS OF THE CLUB. upon the scarcity of the species of Kodiosoma in collections.
9 June, 1893.
The 179th meeting was held
Mr. A. P. Morse read a paper on Wing-
at 156 Brattle St., Mr. S. H. Scudder in the length in some New England Acrididae and chair. exhibited specimens in illustration. Mr. H. G. Dyar exhibited specimens of Mr. S. H. Scudder exhibited a folding net Kodiosoma eavesii collected by Mr. L. B. sent to the club from Switzerland.



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