[Footnote: From the _American Naturalist_, November, 1882.]
THE BUCKEYE LEAF STEM BORER.--In our account of the proceedings of the
entomological sub-section of the A.A.A.S., at the 1881 meeting (see
_American Naturalist_, 1881, p. 1009), we gave a short abstract of Mr.
E.W. Claypole's paper on the above insect, accepting the determination
of the species as _Sericoris instrutana_, and mentioning the fact that
the work of _Proteoteras æsculana_ Riley upon maple and buckeye was very
similar. A letter recently received from Mr. Claypole, prior to sending
his article to press, and some specimens which be had kindly submitted
to us, permit of some corrections and definite statements. We have a
single specimen in our collection, bred from a larva found feeding, in
1873, on the blossoms of buckeye, and identical with Mr. Claypole's
specimens, which are in too poor condition for description or positive
determination. With this material and with Mr Claypole's observations
and our own notes, the following facts are established:
1st. We have _Proteoteras æsculana_ boring in the terminal green twigs
of both maple and buckeye, in Missouri, and often producing a swelling
or pseudo-gall. Exceptionally it works in the leaf-stalk. It also feeds
on the samara of maple, as we reared the moth in June, 1881, from
larvæ infesting these winged seeds that had been collected by Mr. A.J.
Wethersby, of Cincinnati, O.
2d. We have an allied species, boring in the leaf-stalk of buckeye,
in Ohio, as observed by Mr. Claypole. It bears some resemblance
to _Proteoteras æsculana_, but differs from it in the following
particulars, so far as can be ascertained from the poor material
examined: The primaries are shorter and more acuminate at apex.
Their general color is paler, with the dark markings less distinctly
separated. No distinct tufts of scales or knobs appear, and the
ocellated region is traversed by four or five dark longitudinal lines.
It would be difficult to distinguish it from a rubbed and faded specimen
of _æsculana_, were it not for the form of the wing, on which, however,
one dare not count too confidently. It probably belongs to the same
genus, and we would propose for it the name of _claypoleana_. The
larva is distinguished from that of _æsculana_ by having the minute
granulations of the skin smooth, whereas in the latter each granule has
a minute sharp point.
3d. _Sericoris instrutana_ is a totally different insect. Hence our
previous remarks as to the diversity of food-habit in this species have
no force--_C.V.R._
* * * * *
DEFOLIATION OF OAK TREES BY DRYOCAMPA SENATORIA IN PERRY COUNTY,
PA.--During the present autumn the woods and road-sides in this
neighborhood (New Bloomfield) present a singular appearance in
consequence of the ravages of the black and yellow larva of the above
species. It is more abundant, so I am informed, than it has ever been
before. In some places hardly any trees of the two species to which its
attack is here limited have escaped. These are the black or yellow oak
(_Q. tinctoria_) with its variety (_coccinea_), the scarlet oak and, the
scrub oak (_Q. ilicifolia_). These trees appear brown on the hill-sides
from a distance, in consequence of being altogether stripped of
their leaves. The sound of the falling frass from the thousands of
caterpillars resembles a shower of rain. They crawl in thousands over
the ground, ten or twelve being sometimes seen on a square yard. The
springs and pools are crowded with drowned specimens. They are equally
abundant in all parts of the county which I have visited during the
past week or two--the central and southeastern.--_E. W. Olaypole, New
Bloomfield, Pa_.
* * * * *
EFFICACY OF CHALCID EGG-PARASITES.--Egg-parasites are among the most
efficient destroyers of insects injurious to vegetation, since they kill
their victim before it has begun to do any damage; but few persons are
aware of the vast numbers in which these tiny parasites occasionally
appear. Owing to the abundance of one of them (_Trichogramma pretiosa_
Riley), we have known the last brood of the cotton-worm to be
annihilated, and Mr. H.G. Hubbard reported the same experience at
Centerville, Fla. Miss Mary E. Murtfeldt has recently communicated to us
a similar experience with a species of the Proctotrupid genus Telenomus,
infesting the eggs of the notorious squash-bug (_Coreus tristis_). She
writes: "The eggs of the Coreus have been very abundant on our squash
and melon vines, but fully ninety per cent. of them thus far [August 2]
have been parasitized--the only thing that has saved the plants from
utter destruction."
* * * * *
ON THE BIOLOGY OF GONATOPUS PILOSUS Thoms--Professor Josef Mik, in the
September number of the _Wiener Entomologische Zeitung_ (pp. 215-221,
pl. iii), gives a most interesting account of the life history of the
curious Proctotrupid, _Gonatopus pilosus_ Thoms., which has not before
been thoroughly understood. Ferris, in his "Nouvelles excursions dans
les grandes Landes," tells how, from cocoons of parasitic larvae on
_Athysanus maritima_ (a Cicadellid) he bred _Gonatopus pedestris_, but
this he considered a secondary parasite, from the fact that it issued
from an inner cocoon. It appears from the observations of Mik, however,
that it was in all probability a primary parasite, as with the species
studied by the latter (_G. pilosus_) the larva spins both an outer
and an inner cocoon. The larva of _Gonatopus pilosus_ is an external
parasite upon the Cicadellid _Deltocephalus xanthoneurus_ Fieb. The eggs
are laid in June or July, and the larvae, attaching themselves at the
junction of two abdominal segments, feed upon the juices of their host.
But one parasite is found upon a single Cicadellid, and it occasionally
shifts its position from one part of the abdomen to another. Leaving its
host in September, it spins a delicate double cocoon in which it remains
all winter in the larva state, transforming to pupa in May, and issuing
as an imago in June.
It will be remembered that the female in the genus Gonatopus is
furnished with a very remarkable modification of the claws of the front
tarsi, which are very strongly developed, and differ somewhat in shape
in the different species. It has usually been supposed that these claws
were for the purpose of grasping prey, but Professor Mik offers the more
satisfactory explanation that they are for the purpose of grasping the
Cicadellids, and holding them during the act of oviposition.
It is interesting to note that there is in the collection of the
Department of Agriculture a specimen of _Amphiscepa bivittata_ Say,
which bears, in the position described above, a parasitic larva similar
to that described by Mik. It left its victim and spun a white cocoon,
but we failed to rear the imago. It is probably the larva of a
Gonatopus, and possibly that of the only described American species of
the genus, _Gonatopus contortulus_ Patton (_Can. Ent._, xi p. 64).
* * * * *
SPECIES OF OTIORHYNCHIDAE INJURIOUS TO CULTIVATED PLANTS--Of our
numerous species of this family, we know the development and earlier
stages of only one species, viz, Fuller's rosebeetle (_Aramigus
Fulleri_[1]). A few other species have attracted attention by the injury
caused by them as perfect insects. They are as follows: _Epicoerus
imbricatus_, a very general feeder; _Pachnoeus opalus_ and _Artipus
floridanus_, both injurious to the orange tree. Of a few other species
we know the food-plants: thus _Neoptochus adspersus_ feeds on oak;
_Pachnoeus distans_ on oak and pine; _Brachystylus acutus_ is only
found on persimmon; _Aphrastus toeniatus_ lives on pawpaw (but not
exclusively); _Eudiagogus pulcher_ and _rosenschoeldi_ defoliate the
coffee-weeds (_Cassia occidentalis_ and other species of the same
genus). Two very common species, _Pandeleteius hilaris_ and _Tanymecus
confertus_, appear to be polyphagous, without preference for any
particular plant. Very recently the habits of another species, _Anametis
grisea_ Horn, were brought to our knowledge by Mr. George P. Peffer, of
Pewaukee, Wis., who sent us specimens of the beetle accompanied by the
following communication: "The larger curculio I send you is working
around the roots of apple and pear trees, near the surface of the ground
or around the union where grafts are set. I found fifteen of the larvae
on a small tree one and a half inches in diameter. The beetle seems to
lay its eggs just where the bark commences to be soft, near or partly
under the ground. The larvae eat the bark only, but they are so numerous
as to girdle the tree entirely in a short time."--_C. V. Riley_.
[Footnote 1: Vide Annual Report Department of Agriculture, 1878, p.
257.]
BOMBYLIID LARVAE DESTROYING LOCUST EGGS IN ASIA MINOR.--The eggs of
locusts in Cyprus and the Dardanelles, as we learn from the Proceedings
of the London Entomological Society, are much infested with the
parasitic larvae of _Bombyltidae_, though these were previously not
known to occur on the island. This fact shows that the habit which we
discovered among some of our N. A. _Bombyliids_ recurs in other parts
of the world, and we have little doubt that careful search among locust
eggs will also reveal the larval habits of some of the _Meloïdae_ in
Europe and elsewhere. Indeed, notwithstanding the closest experiments
of Jules Lichtenstein, which show that the larva of the Spanish
blister-beetle of commerce will feed on honey, we imagine that its more
natural food will be found in future to be locust eggs. The particular
_Bombyliid_ observed by Mr. Frank Calvert destroying locusts in the
Dardanelles is _Callostoma fascipennis_ Macq., and its larva and pupa
very closely resemble those of _Triodites mus_. which we have studied
and figured (see Vol. XV., pl. vi.). We quote some of Mr. Calvert's
observations:
"On the 24th of April I examined the larvae in the ground; the only
change was a semi-transparent appearance which allowed of a movable
black spot to be seen in the body. On the 8th June about fifty per cent.
of the larvae had cast a skin and assumed the pupal state in their
little cells: the color yellowish-brown, darkening to gray in the more
advanced insect. About one per cent. of the cells, in which were two
skins and an aperture to the surface, showed the perfect insect to have
already come out of them. A gray pupa I was holding in my hand suddenly
burst its envelope, and in halt a minute on its legs stood a fly, thus
identifying the perfect insect.... I found the fly, now identified,
sucking the nectar of flowers, especially of the pink scabious and
thistle, plants common in the Troad. (Later on I counted as many as
sixteen flies on a thistle-head.) The number of flies rapidly increased
daily until the 13th, when the ground appeared pitted all over with
small holes from whence the parasite had issued. A few pupae were then
still to be found--a larva the rare exception. The pupal state thus
seems to be of short duration. It was very interesting to watch the
flies appearing above ground; first the head was pushed out; then, with
repeated efforts, the body followed; the whole operation was over in
two or three minutes; the wings were expanded, but the colors did not
brighten until some time after. Occasionally a pupa could not cast
off its envelope, and came wriggling out of the ground, when it was
immediately captured by ants. Unfortunate flies that could not detach
the covering membrane adhering to the abdomen, also fell a prey, as
indeed many of the flies that could not get on their legs in time. The
flies for the first time 13th June, were seen to pair, but this rarely."
* * * * *