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Psyche 3:411-412, 1880.

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PSYCHE.
THE COCOONS OF CIONUS SCKOPHULARIAE.
BY GKORRE DIMMOCK, CAMBliID(+E, MASS.
The cocoons of Cfom scrop71iiIarii.ie
fnrni4 an illustration of striking simi- larity of form of insect structures to
parts of a plant. Geoffrey1, in 1762,
without, of course, perceiving any cause for this similarity. writes of this species : "When their larvae, after having de-
vonred the leaves of the Seroplinlaria,
have arrived at their full size and are
rea* to transform, they make at the
tip of the stems a sort of slightly trans- parent bladder in which they enclose
themselves and undergo their metamor-
pliosis. This rounrl and quite firm
bladder appears to be produced by a
viscid moisture with which the larvsi
is covered. How can the insect form
this round vesicle with this sort of
glue? This I have been unable to per-
ceive. I have only found the larvae
just enclosed in this vesicle; I have
seen them there under the form of
pnpie, am1 finally tlie perfect insect has come out of them before my eyes.
These vesicles are of the size of the
shells which contain the seeds of the
Scrophnlaria and are often mingled m it11 them ; but the\ are easily distinguid~ed 1 Genffroy, E. L. Histoire :ihregee des insectes qui se trouvent EIUX environs de Paris . . . 1762, v. I, p. 277, 297-
by their transparency and by their ronnd form that differs from the fruit of tlie Scrophiilaria, which terminates ill a
point." Again the same author writes,
"This larva forms at the extremity of
the branches, near the flower-buds a
round shell resembling a bladder, where
it undergoes metan~orphosis and from
which, at the end of several clays, I have seen the perfect insect emerge." The
preceding is the earliest mention I have found of the cocoons of Cionus. About
a dozen writprs have since written notes upon am1 descriptions of ,the cocoons
of the genus.
Hermann Muller2, in 1879, figures
cocoons of C. scrophulu~iae on a sprig
of Scrophdaria nodosa and writes of
them, "We find a still more delusive
similarity of cocoons to other objects,
and indeed in this case to objects imme- diately around them, that is to the
ovaries of the plant on which they are
found, in a common little curculioi~id,
Ciontis scrop7mlcwiae, which feeds in
the larval state upon the leaves of
Scropl~daria 'nodosa and spins itself for pupation into brown oval cocoons on
the blossom and fruit stems of the
2 MUller, H. Schiitxende aehnlichkeit einheimischer in'sekten. (Kosmos, bd. 6, p. 119.)




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PSYCHE.
same plant. These cocoons, placed not, as is often the case with such struc- among the ovaries of the plant, can hires, repellent to water; it moistens scarcely be distiagnislied from them, readily, but these piincttires mostly re- altlio tlie COUOOHS a12 neither pointed main open while it is moist. They fw- nor do they have the cleft which sepa- nish thus an inlet far air, an outlet for rates, even exteriorly, the capsule into the moisture emanating from the pupa two halves."
duriug its n~ctm~s'pliosis, iiud still they The cocoon, as has been miantioned by prevent Hie entrance of water iu rainy other writers, is usually fastened to a. weather; their rarity or absence from
pedicel of one of tlie ovaries just beneath the upper end of the cocoon being appar- the ovary itself, being readily (listin- ently further protection from tlie force guisliablc from the ovary by its trails- of raindrops. Quite possibl~, too, the parency find form, and the end of the protruded margins of the punctures pre- cocooil farthest from the ovary is cnt off vent the entrance of spores of fungi like a rotindish lid liy the beetle in which would be Jujuriotis to the pupa. emerging. Westwood* describes the cocoon of I fiud 110 correct notice, however, of C. scmp1tv,hriae ns "formed with open the little punctures which dot the meshes, like that of the Hyperae." cocoon.
These holes have an appear- This statement by Westwood, prol~1b1-j ance as if pricked from within the made tip011 the aiittiority of Schiiffer4 is COCOOD with a Sw. needle, for their criticized by Osbo~ac,~ who writes, margin is somew hat elevated oiitside, as b4These cocoons are kii'olate splieroids, is the edge of a needle-hole in paper.
lemon-shaped, but not pointed at the
The diameter of the holes the~nselves is emis, inid are q~aruely rovcml in the
0.05 mm. to 0.06 mm., and they are middle region wil.11 misied whitish scattered about on the sides of the 'goose-skin' points, which appear to be cocoon at quite irregular distances from prociucwl by the subsequent fillirg up of each other. On the end of the cocoon small openings left hi the original toward the ovary of the plant, which is making of the eocoon. A COOOOH seen tieuaiiy also the upper end of the cocoon, iu the unfinished state would present these puctiirrs are very rarely to be cribriform openings, ht would not evt 11 found, bnt on the other end of the then be like tire network cocoon of cocoon they arc as ahuticlaut tis tisex are Hypera." &borne writes further : tipon the sides.
"The puirae at first iire extreme1;- dcli- The function of these punctures is, pate, almost like transpnrent glass ; probably, to admit sir to the enclosed
pllpa, for Lhe cocoon-material itself is 3 wesfwood, J. 0.
An intrnduction to the inidern
very firm in texture mil impervious both classification of insi,-ets . . . is=, r. 1, p. 313. to water and to air. The protrusion of 4 SchZffsr, j. C. AbhiiinUnnsen 1011 in-schtcti, . . the miirgin~ of eiich puncture ie appar- '?% '-'' *'^ 8 Osbornc, J. A. On the cocoons formed by ffypsrft "''Y '0 P"'~'" '1" 't'LT'''ce of w'~'.
r,~mjcjs rind its pwaites and CioHMs <<rop,+#~otioc. The exterior surface of the coc'ooii is
( E ~ ~ O ~ , im, mag., 1879, v. 16, p. ift-16 )



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become greenish or whitish and opaque
after some time ; and, if exposed to too dry an atmosphere, both pupation and
the exclusion of the imago are rendered
impossible or difficult. Therefore, I
imagine a close, inembranaceons cocoon
is a necessity ."
I have found, in exaininiiig n large
number of specimens of cocoons of C.
scropL'uhtri'ae, no exception to the exis- tence of punctures in them, altho the
pnnctiires are never large enough to be
termed open meshes. Were it not for
these piirictnres the cocoons of C.
scrophulcwiae would be, to all appear-
ances, hermetically sealed. This is not
the case with the cocoons of bowbi/cidcie, as en11 1)e seen readily, hy covering a
portion of a cocoon with soapy water
and blowing through the portion to be
tested. The unmerons bubbles which
form 011 the outside in such an experi-
ment are clear proof of the passage of
air throngh the cocoon-walls. Even the
very compact inner lining of the cocoon
of Aitacus promethea readily allows the
passage of air.
Treated with dilute acids the cocoon
of 0. scro1)71~ilaricbe shows little change ; alkalies dissolve out of .it, as they do out of cocoons of bom'bycic7ae and even
out of portions of insects themselves, a brownish-yellow coloring matt8er, which
loses its color on being acidulated, and regains it 11pon again making the solu-
tion alkaline. The whole cocoon of C.
sc~~o1)7~1~1~ric~e is soluble in strong nitric acid.
NOTES ON PTEROPHORIDAE OF NORTH AMERICA. 2. 13Y GEORGE DIMMOCK, CAMBRIDG b:, MASS.
In the list of references concerning
ptorophorida? which I published in
~'SYCHE, Sept.-Oct. 1883, v. 3, 11. 402- 404, I o:n'ittecl, by some accident, all referencss to a paper published by Dr.
D. S. Kellicott in tlia Bulletin of the
Buffalo society of iiiitural seienc?s for Janiiay 1832, aufl afterwards as a
separate. Wishing to make my notes
:is complete as possible I add the follow- ing data token froin that pilp2r. th? title of which is "Notes on tli~liirvi~e of some local pteroy^orirtde."
P/cr/y//i/zt-s cardnidncfyliis Rile!. Kelli- colt (Bull. Buffalo soc. nat. sci., Jan. 1882, v. 4, p. 47) gives notes on the larva and pupa of this species, and states that it is often parasited by a variety of Ichneumon Jinmilis, Provancher.
Oedematophoruy, crc//~Ic~c/ylu.~ Fitch ( I st and 2nd Repts. nox. ins. N. Y., 1856, p. 142). Kellicott (Bull. Buffalo soc. nat. xi., Jan. 1882, v. 4. p. 48-50) describes the larva and pupa of this species. The gregarious larvae feed upon E'ipa/o~i//m purfurearn, the
leaves of which they fasten together with a web.
N. Y., Cal., Vancouver's lsl.
Lio/ti/ns homodacfylus Walk. Kellicott
(Bull. Buffalo soc. nat. sci., Jan. 1882. v. 4, p. 48-50) describes larva and pupa of this bpe- cies. The gregarious larvae feed airong
leaves of E@ato;,///~~z fz~yzhmiini which they have webbed together.
Buffklo, N. Y.
Aciptilus 7izontanm, Wlsm. Kellicott
(Bull. Buffalo soc. nat. xi., Jan. 1882, v. 4. p. 51-52) describes 1 arva and pupa; the former feeds upon the leaves of different species of SoJidago. Buffalo, N. Y.




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