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Psyche 3:207-210, 1880.

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PSYCHE.
SOME PSOCINA OF THE UNITED STATES,
BY HERMANN AUGUST HAGEN, CAMBRIDGE, MASS. (Continued from f. 796.)
Genus ELIPSOCUS.
THE genus Elipsocus is a very natural
one.
Mr. Kolbe has separated E. uni-
pwnctatus from the rest as belonging to
a different genus Mesopsocus Kolbe.
This species, it is true, has a peculiar facies, nevertheless the differences do
not appear to justify a generic separation, the more as a new species E. laticeps
Kolbe is perhaps only a variety of E.
un@unctatus. Both have no hairs on
the veins of the wings, which is an ex-
ception in Elipsocus. The differences
quoted by Kolbe for Mesopsocus consist
chiefly in the venation, and represent
differences found as variations in the
same species. Among thirty European
specimens now before me, twenty have the venation of Hesopsocus (alarm anti-
carurn rams venae medianue interior
rmusque venae submedianae exterior
venula Lransversali conjuncti, Kolbe) ;
the other ten specimens have both rami
united in a point (without the ve'nula
tronsversalis) ; one of them has the
rami confluent, as figured by Spangberg, and described as a character of E. lati- wps by Kolbe. The other differences of
the venation quoted by Kolbe are even
less important, and occur likewise in
E. unipunctatus. I may state that my
specimens are from Sweden, Eastern
Prussia, Saxony, Posen, Hamburg, and
Elberfeld, and that the before mentioned varieties were found together with the
normal form.
The claws of the legs of E. kpunc-
,
tutus have a tooth below, before the
point, only visible with the compound
microscope. The claws are 0.05 mm.
long, the tooth 0.003 mm. The basal
third of the claw is enlarged below,
forming a prominent edge. I remark
that the nearly related genus CaeciUus,
except Pterodela, has no tooth on the
claws in living and fossil species, and is, as far as my observation goes, the only
one with toothless claws. The genital
appendages of the male of E. unwunc-
tatus are covered by alarge spoon-shaped valve, which is bluntly pointed above;
the appendages black, somewhat in-
curved, narrow, truncated on tip ; the
external border truncated in the middle, therefore not reaching the tip. The
penis appears to be long and stilletto-
shaped.
In the Synopsis of the Neuroptera of
North America, p. 9, at no : 3, Psocus sig- natus, I have stated my doubts concerning the distinctness of this species from Ps. innbunis Steph. (= unipunctatus) . There are before me five specimens from Massa- chusetts and New York, which, after a




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208 PS KHE.
very detailed examination, I am unable ago, but did not examine the ocelli, to separate from the European apecies. which are very easily overlooked with- The slight differences of the venation, out the use of a compound microscope. spoken of before, occur also among the The rudiments of the wings are small North American specimens. The idea- ovoid scales, attached to the external tity of the species is made more sure by margin of the mesothorax and to the
the fact that short-winged specimens are metathorax with a very short stem, and
found in Europe and in -North America, not with a broad base as commonly in and that till now E. ~~~aipunctatus is the the nymph state. The scales lie close
only species of which short-winged aim-
to the thorax and are scarcely longer
hens are known. I possess three spec-
than the segment to which they belong ;
hens from Eastern Prussia, found to- they are opaque, chitinous, only the gether with the long-winged specimens,
apical half thinner and somewhat trans-
and two from New York, which I parent, yellow as the main color of tile received together with the types of Ps. body of the iiisect, without veins, but sf pt atw .
with a darker middle stripe ; the border Mr. Kolbe is inclined to doubt the around the scale somewhat thicker. existence of short-winged specimens The head of the abort-winged sped- (Monogr. deutsoh. Psociden, p. 951, and mens and the large eyes are similar to therefore I may give here some more those of the normal form, excepting the detailed information- The specimens want of the circular elevation bearing agree exactly with the figure given by
the ocelli. The antennae hairy but thin- Westwood, Introd., v. 2, f. 59, no : ner. Size, body and legs as in the normal
13, 14, 1s. The only difference is the
form. The genitals are not to be ob-
absence of ocelti according
to West- served surely in the dry specimens, but wood's statement, but I think that prob- seem to be similar to those of the normal ably he used a leus of low power.
The form.
Une is surely, three are probably
ocelli are easily seen with the compound male ; oue seems to be a female, and the microscope; they do not stand upon a eyes are more separated. I think the
oirealar elevation as id the long-winged appearance of such sljecimens is by no specimens, but upon the flat surface of meaus exceptional, as similar short- the head.
The cornea is very little con- winged images = known to exist among vex, but sharply defined around its the termitinu and perha. They are border, and shining ; the anterior oceilus imago8 with rudimentary wings. is smaller, and in one specimen the I remark that I had accepted for the cornea ifs like a dull mmhane. species the name E. apkidwdes Schrank, another specimen this ocellue is deepened, because it is doubtless sure, though but Ì small shining cornea is visible in Mneller's name E. u?~@unctatus, the the hole. The diameter of the two pos- idei~tificatjon of was firat pointed terior ocelli is 0.04 mm. ; the anterior out by myself, is only probably sure.
is smaller. I saw Westwood's type years




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PSYCHE. 209
PSOCKS wenosus Bum.
The species is found everywhere from
Canada down to the Gulf of Mexico and
occurs also in Citba. I do not know
whether it is found west of the Rocky
Mountains or not. It appears to live
gregariously, sometimes in large num-
bers, on apple trees, in all different
stages. As it is here the largest species, I have tried to study it carefully, and
give here a short notice of some entirely new pharactei's, which may be observed
partly in other species.
The wings of ~soews have mostly
been treated of in a rather summary
manner. The venation is considered in
ii different way 1iy different writers, but a satisfactory study of the species not
belonging to the European fauna has
thus far been wanting, and such a study
will probably lead to better knowledge.
I use here, for convenience, the iio~ncn- chtnre idopted by Mr. Kobe in his new
monograph, reserving until a future time and as the result of farther advanced
study, the introduction of some chmges.
I would here draw attention to a few cliar- rtcters, which I find nowhere mentioned. 1. At the extreme base of fore and
hind wing of Psocus vmwus (and several
related species), just below the the nth- costa. there is a darker. more chit.iinous place, boi~lerecl below by the median
vein and ending iu front about where
the submediaii begins. Examined with a
rather strong lws, this place (0.2 mui.
long) has the appearance of a sieve
with numerous round holes of 0.003 mm.
diameter, arranged in a series of lougitndi- iial lines, not strictly keeping in the lines. lu changing the focus, every hole is found to have a small sensitive bristle in the centre. The whole arrangement is simi-
lar to that 011 the base of the wings of cliptera or on the antennae of insects,
described loug ago. and presumed to
represent the sense of hearing. I have
hitherto been unable to prove the pres-
ence of nerves and ganglia in this place, but such will be found without doubt.
In full grown uymphae I was able to see
the same an'angemeut, but in a less
definite shape. The small holes have not such sharp borders in the iiymphae as in the imagos, and the middle elevation
seems to be larger than in the imago.
2. The wings of full-grown nymphae,
while still contained in the wing case,
show nearly the whole venation indicated by paler lines, representing the veins,
which are blood vessels. Around the
margin of the whole forewing runs a
broad sinus (0.016-0.023 mm.) , with
which the other veins are connedited.
The whole wing is dull, not hyaline, pale grayish, densely filled with cells. The
tracheae are very small (0.0017 mm.
dinmeter against 0.005 in the imago),
often only indicated, and the spiral thread not visible or replaced hy transverse
nuclei. In sin earlier stage there is fouud as the first indication of a trachea, one series of cells arranged in a band. The
trachea forming the analis of Kolbe is
iilw~js broader (0.0025 mm. diameter,
against 0.03-1- in the imago). The
analis belongs to the underside of the
wing and is. as far as I know. the only
one not accompanied by a blood vessel,
and formed only by a trachea for pur-
poses later to be spoken of. The bind
border of the wing case has two series




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210 PSYCHE.
of long bristles (0.104 mm. long).
poudiiig one of the lower membrane in
Specimens just after transformation a loop at the margin. I have to remark show the wings hyaline but somewhat
that the tracheae seem only in juxtapo-
milky.
The larger veins and the ptero- sition to the Mood veins, at least I have stigma, are filled with a. large number of established this undoubtedly in the case blood-cells. The two membranes of the of the mediana. A more detailed study wings, even in the imago state, are less of the origin of the veins will probably firmly glued together than in other give a more certain basis of facts for insects, and easily separated if the wing identifying the value of the veins, and is touched roughly or glued with one for contributing to a better founded aide on paper or glass. The membranes nomenclature. For instance, the ramus of the hind wings are still less firmly con- medianae interior in the hind wings is
uected than those of the forewings.
la united with the ramas submediauae ~xte- going through a moderately large collec- rior at the base of the wing, and both
tion of Psows, specimens will be found
can only be considered to be the two
showing a separation of the two mem-
branches of the same vein.
In the fore-
.
brauea at least in some parts. The same
wing the ramus mediauae interior is a
is often to be seen iu fossil species branch of the mediaua and the ramus sub- included in ahher or in copal. mediame exterior a branch of the subme- All veins show numerous short iip- diana. The mecliaua originates from the pressed hairs, the longest on the rtiargi- anterior basal wing-callus, the snbmedi- ~al vein around the wing (0.009 tnm. ana from the posterior wing-callus; nev- long). The only vein without any cloth-
ertheless bofcb veins are connected by a ing of hairs is the analis. The whole tracheal loop at the extreme basis of the membraue of the wing is beset more or wings. I have purposely gives this in less densely with similar but much smaller such detail, because the whole disagree- hairs (the longest 0.003 mm.). ment about the nomenclature of the veins It is a fact new to me that the between McLarlilaia and Kolbe consists whole venation, with the exception of in this point. Bnt I have not yet ih- the subcostalis and analis, consists of it ished
studies to a point satisfactory
donMe net, not only of wins, as 1 have
to myself, so as to emit a positive opinion proved long ago, but also of tracheae,
about those veins.
one net belonging to the ripper mem- The somewhat loose connection of the braae, the other to the lower on@.
Both
two membranes of the wiugs, aud the
are exactly alike and caimot be seen fact that the tracheae are double and when the two membranes are firmly glued
constitute, -for a very large part, the
together. When separated, which OC- venation, easily explains the very fie- curs more easily in the bind wings, both quent variations and warns tis to use such nets are clearly visible, and each trachea differences only or chiefly for generic of the upper membrane joins the corres- separation. ( To be co*~t inwd .)




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