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Psyche 4:303-304, 1883.

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PSYCHE.
NOTES ON MELITTIA CUCURBITAE AND A RELATED SPECIES.
BY SAMUEL HUBBARD SCUDDER, CAMBRIDGE, MASS. THE tolerably full account of Melittia
cucurbi/ae recently given by Mr. J. A.
Lintner in his second Report on the
injurious insects of New York recalled
to me some observations made on the
ravages of this insect in the squash
vines on Cape Cod, and from my notes
made at the time, now more than
twenty-five years ago, I condense the
following statement.
My examination was made in the
early part of September, and there were
to be found at that time two kinds of
aegerian larvae within the plants, a
larger and a smaller, and in the ground
were found cocoons containing larvae of
the larger kind-which subsequent ob-
servation showed remained through the
winter without changing to chrysalis,
and also a number of pupal exuviae
protruding from the surface of ground
which had not been hoed for a month
or more.
There are thus apparently two species
of aegerians destructive to the squash,
and it seems to be probable that the one represented by the smaller larvae and
the chrysalis-skins is either a later ap- pearing species or that it is double-
brooded, the brood represented by the
smaller larvae in September being the
later, There can be little doubt that
both were aegerians, as they agreed
closely in all structural peculiarities, and they could hardly have been difler-
erent stages of the same species, since
they differed so much in the color of the head and thoracic segments and in the
general markings. The following des-
cription of the larva of M. cucurbifae,
fuller than before published, is drawn
up from my notes.
Head very dark brown, deepening into
black, with a median white band reaching to the frontal triangle and passing down its sides ; a few scattered hairs are seen. Body white, the dorsal vessel visible through the cuticle, the surface smooth, but with two or three hairs on each segment, and on the terminal segment some faint light brown spots and four backward-projecting hairs. The first thoracic segment has on the dorsal surface two oblique, curved. light brown bands.
nearly meeting posteriorly, their concavities outward; between their extremities on the front of the segment are a pair of transverse, almost microscopic, semicircular lines open- ing forwards. On second and third thoracic segments (my notes fail to say whether above or below) a transverse row of hair-bearing, scarcely perceptible, tubercles. Legs light brown ; in place of prolegs, rings of black bristles. Spiracles light horn-color, sur- rounded by white, and this by a horny areola. Length 25 mm; breadth a little more than 6 mm.
As this and the smaller larva were at
first taken for different stages of the
same species, the difference in their
habits was not so carefully noted as it
should have been. The present species
was, however, by far the more destruc-




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304 PSYCHE. [ July-September 1885.
tive, being ten times morenumerous than
the other ; nearly forty were taken from the inside of a single plant, they being found concealed in all parts from below
the ground as far as they could burrow,
to the base of the leaf stalks, and some were even in the squash itself; besides
these, in the hill in which the same
plant was growing, over twenty larvae
were found in their chrysalis cases.
They cast most of their excrement
through holes eaten to the surface of
the stalks. They appear to commence
their work near the surface of the
ground, and to work their way in each
direction.
When ready for their change, they
eat their way out of the stalk, reach the ground (probably by a thread, for they
can spin one) enter the ground and make
their cocoon there ; this is formed exter- nally of grains of earth adhering to silk, and is of considerable stoutness though
very thin ; it is of a light brown color within and blackish without, so that
when the earth is removed, the cocoon
has a reticulated appearance, from the
brown showing through the black ; the
innermost layer of all is white. Some
of these cocoons were kept, and the
larvae were living within them on the
26tn of the following May, having re-
mained unchanged in the larval con-
dition throughout the winter. They
subsequently died. Thirty or forty
cocoons were opened in the hills only
to find the larva within.
This is all the history of this species
which was followed. The second spe-
cies has very nearly the same habits,
excepting that it perforates the base
of the leaf stalks themselves and lives in the leaf stalks, often curled up. M.
cueurbitae was also found there but not
so frequently, and the present species
seemed to prefer in addition the harder
parts of the plant, such as the junction of the leaf and stalk, of the leaf stalk and main stalk, etc. The following is
a description of the smaller species.
Head jet-black. Body white, with a faint, dusky stigmata1 band. Upper surface of first thoracic segment nearly black ; a transverse series of eight brown spots on each segment behind the first, two faint ones being dorsal, one on each side infra-stigmatal, and the others pleural ; those of the thoracic rings are much the most conspicuous, and on the abdominal rings there is a brown dot on each ring in front of and a little within the dorsal spots ; the last segment is brown above with spots similar to those of M. c~c26~bitae but more distinct; hairs as in that species. Length 13 mm. ; breadth 2.5 mm.
No difference was noted between the
cocoons beneath the surface with living' larvae (LV. cucurbitae) and those of
the present species which were emptied,
the chrysalis forcing off (how ?) the en- tire end of the cocoon, and by means
of the hooks on the abdominal rings
working its way to the surface. A
single larva, kept in captivity, made a
cocoon in a small box partly filled with earth, and it was noted that the cocoon
was thinner than that of M. cucurbitae.
Brief additional notes on M. cucur-
bitae will be found in Papilio, v. 2, p. 50, by N. Coleman ; and in Bull. Brook-
lyn entom. soc., v. 6, p. to, by G. D.
Hulst.




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