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Psyche 6:173-175, 1891.

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November 1891.1 PSYCHE.
THE EARLY STAGES OF THREE COLEOPTERA.
BY SAMUEL H. SCUDDER.
Finding among some old papers
notes of the early stages of certain Col- eoptera imperfectly known, I venture to
print them. All the species were
found upon sweet fern.
MEGILLA MACULATA.
The full grown larva has the head shining black, faint yellowish in centre. Body black above, brown beneath, except two yellow
spots on the edge of the fifth abdominal seg- ment; first thoracic segment with transverse yellow bands at front and hind edges; the second and third with a yellow dorsal stripe ; second abdominal segment, except the mid- dle third, yellow, fifth abdominal wholly yellow, and the other segments with a row of yellow spots on each side. Besides there are twelve longitudinal series of black pa- pillae, six on the upper and six on the under surface, one to a segment in each series, those on upper larger than those on under surface, each giving rise to a short black hair.
The pupa is in general black.
Head with
a median yellow line. Thorax with a dorsal yellow stripe, a median transverse band and a stripe at the sides reddish yellow; from these a dorsal and lateral stripe of the same color pass backward and broaden in the mid- dle of each segment, the first abdominal seg- ment thus entirely reddish yellow except a subdorsal black spot on either side; besides in the interstices of the abdominal segments are other minute yellow and black spots; the thoracic appendages are black and the mark- ings of the elytra of the future imago cannot be seen; ventral surface of abdominal seg- ments white.
The hind legs protrude oddly on
either side of the body beneath the'
elytra like two side horns, and the legs- of the cast larval skin sprawl about the tail of the chrysalis, the last segment
being immersed therein. When quiet,
the chrysalis lies on the surface of rest, but if disturbed, it erects its whole body at right angles thereto, and then the
interstitial markings of the abdomen are concealed. One individual changed to
chrysalis on August 24. (Notes of
1859.)
The full grown larva has a small black
head and a dusky body; in the middle of" either side of each thoracic segment is a large black spot, covering nearly the whole surface on the first segment which is bor- dered anteriorly with dull orange; there is a dull orange dorsal band of irregular width' along the whole body, its limits vague, and besides, on the abdominal segments, subdor- sal, lateral and stigmata1 series of black spots, one to eich segment; on the sides of the first five abdominal segments arefound some dull orange spots; thebody beneath is dusky with a rather dull orange broad ventral band ; the legs are black.
Length g mm.
The pupa is in general of a dusky yellow; the head is black; thorax with a yellowish dorsal line and on either side of it at the posterior edge of each segment a black spot; the first thoracic segment has also another lateral black spot on posterior edge and a large black spot on the front edge ; the wings. and all the thoracic appendages are black where exposed ; but otherwise apparently dusky or pale yellow; the abdominal seg-



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[November 1891.
ments are dirty white or black with yellow- ish spots, the first two segments having a predominance of yellow, the others of black; the ventral surface is dirty white or yel- lowish.
Two specimens changed to imago on
September 10th at Cape Cod after eight
days in pupa.
(Notes of 1,861.)
The pupa is figured by Comstock
(Rep. U. S. entom. for 1881, pl. 18,
fig. 4) and the larva by Candhze (Mem.
soc. sc. Li6ge, vi, pi, 6. fig. 7.).
CHLAMYS PLICATA.
The larva of this beetle may be found
abundantly the last of July and early
in August hanging perpendicularly with
its case from the under side of leaves of sweet fern.
It has an orange yellow body, deepening
in tint toward the tail with a delicate suffu- sion above of light olivaceous green, but the head and long legs are jet black, and the dorsum of the thorax and the parts above the legs are of a dark testaceous. The whole body is sparsely covered with microscopic hairs, and one notes a depression in the middle of the dorsum of the last segment. When
taken from its case the tail is
curled under its body and this is evi-
dently its normal attitude.
The larval cases are from five to six
millimetres long for the full grown
creature, and at the most about three
millimetres broad. They are smooth
within but externally rough, black,
oval, the oblique open end generally
minutely flaring with a more or less
distinct notch above and below, and
especially below, for the better use of
the legs; it looks as if made of black
papier mach6 and is evidently formed
by accretion, as may best be seen by
examining the under surface where there
is an indistinct median groove, where
the bands of accretions on either side
seem to have been brought together.
These accretions are laid on apparently
at about ten or twelve times during the
life of the larva, in an oblique course, broadest on the back and narrowest on
the ventral side. According to Riley
and Murtfeldt it has as its basis "a cov- ering of dark sticky excrementitious
matter . . . somewhat bell shaped, the
upper end being largest, squarely
docked and slightly depressed so as to
form a circular rim around the margin"
which the female constructs to cover
the egg, and which is cut away from
its attachments by the larva when born
and made the basis of its movable
house. The manner of enlargement
has yet to be told.
The larva crawls with some rapidity,
and when it retreats within its case it is wholly beyond the deepest cleft, the
claws of the feet only projecting there- from. When one is forcibly removed,
it seems unable to get back again ; at
least such as I have experimented upon
have failed to do so, though they tried
hard to do so by going in head fore-
most ; they succeeded in getting only
the head and three of the legs inside,
the length of the legs appearing a
hindrance.
Before changing to pupa they turn
around in the sac so that the anal ex-
tremity is toward the former opening,
which is now closed, since in prepara-




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November 1891. ]
PSYCHE.
tion for the change they glue this end
tightly to the surface of a leaf, and with such a superfluity of substance as to
make this end of the interior rounded.
At first the pupa retains the bright yellow color of the larva, the eyes and tips of the mandibles being black, and the outer surface of the legs and wings and especially the in- cisures of the legs infuscated. Afterwards when nearing the final change, the pupa as- sumes the color of the beetle, a brilliant deep bronze, though the abdominal rings, espec- ially at the tip, still retain somewhat of their original yellow.
The pupal state lasts nearly four weeks
in Massachusetts, in one instance from
Aug. 4 to Aug. T.O. The pupa seems
to be free, moving at least its head and hinder legs with ease ; in the change
the old skin is thrown off as a thin
transparent pellicle, which looks as if
only large enough to cover the end of
the abdomen, while the old larval skin
may be discovered packed tightly away
next the old opening. By using its
jaws upon the end of the case with
which they are in contact, the enclosed
beetle succeeds in making little trans-
verse cuts around the former bottom of
the sac until finally the old egg-covering with a little more is lifted at the single part of the bitten circle remaining as at a hinge, and the beetle presents himself with all his fresh beauty to the world.
I once found on July 15 a case glued
to a fern leaf, and noticing a series of fine holes around the glued end I opened it and discovered the larva in position
for change to pupa, but lying against its middle the pupa of a hymenopterous
parasite of a uniform light amber color
with deep amber eyes and about I .75
mm. long. Five days later I noted
change in color and discovered that the
body of the Chlamys larva was simply
crammed with similar hymenopterous
pupae, twenty-three in all ; three days
later they emerged, but unfortunately
were never determined and are now
lost. When the pupae had gained their
color, however, the dorsal portions of
the abdominal segments were very dark
brown, almost black, with a few indis-
tinct transverse yellowish streaks and a similar streak across the thorax just
behind the head ; there are three ocelli in a row on the top of the head between
the eyes ; the hind legs just reach the
tip of the abdomen but the other legs,
like the hind legs appressed to the sides of the body, are short.
Other larval cases similarly attacked
were found where the parasites had left
the case ragged at the end opposite to
the glued part where they had made
their escape.
There are apparently at least two
broods of this beetle which I have found in the latter part of July and in the
latter part of August and early in Sep-
tember. Probably the beetles hiber-
nate. (Notes taken in 1859-1861 .)
The larva and its case are figured by
Riley (Rep. ins. Missouri, vi, fig. 37
on p. 130).




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