Article beginning on page 103.
Psyche 4:103-106, 1883.

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PSYCHE.
A NEW SEXUAL CHARACTER IN THE PUPAE OF SOME LEPIDOPTERA.
BY JOSEPH ALBERT LINTNER, ALBANY, N. Y.
[Read before the American association for the advancement of science at its Montreal meeting, August 1882.1
The sexual characters of insects
have always been an interesting study
to the entomological student, the more
so as they are the less apparent, and
discoverable, if to be found at all, only as the result of close observation and
comparison. In the larger proportion
of insects, in the perfect stage, they are so marked as to leave no doubt of the
sex when the male and female are com-
pared. Thus, in the hymenoptera, we
hme the ovipo~ito~ in its varied forms,
often quite conspic~~ous. In the lepi-
doptera, among the heterocem, there are
usually the more fully developed anten-
nae of the male, and the broader, conical and more capacious abdomen of the
female-features attaining- their maxi-
mum development in the family of
bombycidae. In the diptera, there are
the larger and more approximate eyes
in the male, and conspicuous structural
differences in the antennae and suctorial apparatus in some of the families. In
the coleoptera, there are often, in the
male, stouter legs, broader tarsi, greatly elongated mandibles and other horn-like
capital and thoracic processes. In the
hemiptera, the vocal organs in the
cicadidae, the ovipositor in several of
the families, and the great sexual differ- ences in size and in the presence or
absence of wings are prominent features. In the orthoptera, there are the stridula- ting wing-nerves, the extended oviposi-
tor, and a genital armature greatly varied in its adaptation to greatly differing
habits. And in the newoptera, dis-
tinctive male characters are found in
clasping organs, in differences in color and in size, the long mandibles of
CorydaZus, the abnormal location of the
intromittent organ in ZibeZZzilidae, and in the elongated and forcipated genitalia
of Panorpa.
In addition to such primary features
as above noted, there are numerous sec-
ondary ones, which do not appear to be
so dependent upon sex, and many of
which seem almost to serve no higher
purpose than that of ornamentation.
Yet it is reasonable to believe that most of these differences have their use in the economy of nature, and that they aid
in the continuance of the species.
~m"on~ such minor antigenetical fea-
tures, may be mentioned, in the lepi-
doptera, the usually more angulated
wings of the male ; the simple frenulum
of most of the male heterocera in con-




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104 p.9 rcKE. ['November-December iS5p
trast with the compou'nd one in the ous and less conspicuous. They rarely female ; the hairy anterior legs of occur in the first stage-that of the egg, Grujta and Vanessa in the -ha-
or more properly, they have not, in
Udae; the long hairs between the costal many instances, been recognized by us.* and subcostal nervures, above the cell It was for a long time believed that of the hind wings of Argynnis, appear-
in the larva of one of our qhingidae not in^, when extended in the cabinet, like unfrequently met with- Thyreus ahhotii a long fringe to the inner margin of the -the sex was so clearly indicated by
front wings ; the incrassated, black scale- difference in color and pattern that it patch upon the middle of vein 3 (the
could be told at a glance.
Of the two
i st median nervule) of the secondaries greatly differing forms, the one marked of Danais; the ovoid discal spot on the with a series of large yellow-green front wings of many of the theclime; in patches on the dorsuni extending half- the kesperidae, the reflexed costal mar- way down the sides, and with another gin in most of the J^isoniades, JBuda- row of smaller subtriangul'ar similarly mus, and Pyrgus,
arid the tibia1 epi- colored spots resting on the prolegs, was --
physisl of the anterior legs in all but one described by Clemens as the male ; the
female being reddish-brown throughout,
of our genera ; the transverse discoidal stigma on the primaries of the larger
portion of our pamphilas, the beautiful
and peculiar microscopic (often con-
cealed) scales, or iindroconia, of many
of the butterflies ; the usually concealed pair of extensile anal appendages found
by Fritz MQEler and ohrs in certain
glur~co$idae, bombycidae, noctdd@e
and in a Danais;^ each of these indica-
ting the male sex. Features equally
interesting, and alike serving no pur-
pose so far as known, might be men-
tioned in each of the orders of insects. In the earlier stages of insects (egg
and larval), sexual features, as would
naturally be expected, are less iiumer-
1 Gnende: Hist. nnt. ins.,
1858-Lepirl., v. -*- Ntict.,
, p. xxxv. Speyer: in Cmad. entonsoi., 1878, v, in, p. 134. Eduarda' CaL-il. lep. Amer., 1877, p. 61). Fritz Miller: Nature, I 1 June 1874, v. 10, p, 102 (Psyche, Mch.-Apr. [9 fuly] 1877, V. 2, p. 24), Morri- EOM : Psyche [g] Oct. 1874, v. I, p. m-n. Sieivers : Cma- state museum
4-116, and has
other writers.
.- '.^ 3' a ^i-Lin. ^C
with a dark brown subdorsal stripe and
numerous short broken striaea4 This
sexual determination of Clemens was
accepted by me in my paper upon the
larvae and pupae of this species in the
26th Report of the N. Y.
of natural history, p. I 1
also been followed by
That the two forms arc ii~iicauve ui
sex, has since been deiiied,6 and it is to be presumed that the denials are based
upon results obtained in rearing them
to their perfect form. The green-
spotted larva may therefore be accepted
as a dimorphic form, comparatively
-*In ~b~//&rru, the eggs which we tn prduce males and FerntUt;~ may he known by their difference in size. See Riley's Aniiuiil reportsofthe skate entomnlt~ gist nf Missouri: 6th, p. 41 ; ph, p. g迢 fl; 8thp p. 158, 4 Two colored figures of the lartae in my possession, ninde by Dr. Cleinens, slinw the sexes the reverse {if this淘th green-spotted me, maikcd its 9, beioe mucli the Iiirger of the two.
f. iL-t^...~.^ ' r.tn.la




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November-December iW.1
rare in my own collections and in the
examples that have come under my
observation.
The young collector of insects learns
very early the simple method of determi- ning the sexes of his Luna, Polyphemus,
Promethea, and Cecropia pupae, and
of many other bombycid pupae, by
observation of the comparative breadth
of their antenna1 cases.
A means by which the sex in the
pupae of the spkingidae may be infaili-
bly named, was pointed out by me in
the Proceedings of the entomological
society of Philadelphia, 1864, v. 3,
p. 654. I have since found the same
characters applicable to the noctuidae
and to other heterocera.
Dr. C. V. Riley, in the Transactions
of the academy of science of St. Louis,
1873, vol. 3, p. 138-129, and in the 6th annual report of the state entomologist
of Missouri, for 1873, 1874, p. 131-132, has described and figured sexual differ- ences in the pupae of'Pronuba yuc-
casella, consisting, mainly, in the great- er length of the "dorsal projections" on the several segments of the male, in the length of the last two segments as com-
pared with those of the female (its
shorter nth and longer lath), and in
its less rounded apex. He says : "sex-
ual distinctions are very rarely observa- ble in chrysalids ; but after I had learned to distinguish between them, I could
readily separate the sexes in this case, and my judgment was confirmed upon
the issuing of the moths."
A few years ago I discovered an in-
teresting feature in the armature of the species of Cussus, by which the sex
PSYCHE, 105
may at once be determined.
I have,
hitherto, withheld its publication, until I had studied others of our spined pupae and could illustrate this feature by proper figures ; but the opportunity for this has not been found, and I accordingly defer
no longer calling attention to it, that the observations of others in possession of
more abundant material may supple-
ment the few that have been made by
me.
It is known to lepidopterists that
most of the pupae of the species of
moths which in their larval stage live
in the interior of stems of plants and
trunks of trees (endophytes), are armed
upon their abdominal segments with
transverse rows of teeth or spines, by
the aid of which, when they are in
readiness for their final transformation, they gradually work their way through
the outer packing of their gallery and
the bark, project their anterior segments to at least one-third the entire pupal
length through the opening, and hold
themselves securely during the eclosion
ofthe moth.
This useful armature in the cossi=ac,
and in such of the aegeriidae as
I have had the opportunity of ex-
amining, consists of two rows of
spines upon most of the abdominal seg-
ments, dividing them, when seen in
extension, in three nearly equal parts.
In Cows robifiiae, the species of the
cossinae with which we are probably
the most familiar, these rows occur on
the fifth (the first stigmata1 segment
posterior to the wing-cases) and the
following segments.
In Cussus yuerciperda alone of the ,




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6 10 P迢s TT/$E. [November-December 1883. species known to me, they commence
in a single row of minute denta-
tions on the fourth segment. The prin-
cipal features of this armature are the
following :-It is always the stronger in the male sex-conspicuo~~sly so in C.
robiniae, but less so in C. center-
ensis : the teeth increase in size from
the fifth to the tenth segment: tlie
anterior row is always the stronger in
each sex ; upon the fifth and sixth seg- merits, it does not, in its lateral exten- sion, reach below the stig~na,~ while
upon the following segments it passes in front of the stigma and quite a distance beneath it : the posterior row is discon- tinued before reaching the line of the
stigmata : the teeth show irregularity in form and size, particularly those of the posterior row.
The sexual distinction above referred
to, presented in this armature, is this : in the male pupae two rows of teeth occur
on segments five to ten inclusive ; in the female, two rows on five to nine inclu-
sive. In other words, the male $@a
shows TWO rows of teeth on segment
ten^ where the female shows but ONE.
In each sex, the eleventh and twelfth have but a single row. Disregarding, as I
think we should in ordinary usage, the
subdivision of what is usually known as
the terminal segment, into demi-seg-
inents, or a segment and a subsegment,
and that still farther refinement which
would make of the extreme portion
an additional segment with full numeri-
cal designation, then it will serve to
prevent misapprehension of the parti-
6 In C. centerensis it reaches below the stigma on the sixth.
cular section showing the sexual feature, if we indicate it as the antepenz~ltimate segment. It would be the eleventh, if
we comn1ence enumeration, as some of
our entomologists do, with the head, but the tenth, if, as seems to me more pi-o- per, we begin with the first thoracic
ring.
Beside the cossinae, this same sexual
feature occurs in the aegeriidae. I am
not able to say if it extends throughout the entire family. At the time of this
present writing, I have at my command
only the pupae of Aegeria exitiosa and
A. ti'iliformis, and it exists in each.
It probably occurs in the pupae of
Zeuzera (one North American species
described), in which the two rows of
teeth are found on several of the seg-
ments, and perhaps also in HepiaZus,
the pupae of which (unknown to me)
are characterized as very similar to
those of Cossus.
Another interesting fact connected
with the armature of Cossus is that the
form, size, and position of the teeth vary to so great an extent in the different
species, and show such distinctive char- acters, as to afford excellent specific
features.' I would not hesitate to pro-
nounce upon specific identity, upon an
examination and comparison of the
pupal armature alone.
7 For comparison with other species of the cossinae it may be stated that an example of C. centerensis 3 has thirty-eight teeth in the anterior row of the tenth segment, and twenty teeth in the posterior 'ow -the latter, in their entire range, occupying a transverse space equal to that of nine teeth of the anterior row. The teeth are black, shining, irregular in size, and are slightly bent upward over their base; their length and the distance between their tips exceeds their basal width




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