Article beginning on page 393.
Psyche 5:393-395, 1888.

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and one-half times the length of the
insect. Legs rather pale, tibiae and
tarsi infuscate, rather densely set with silvery hairs. Wing's beautifully iri-
descent and rather sparsely set with
long gray pubescence, fringed all the
way around; costal and first longi-
tudinal nervures rather heavy and united at the apex of the wing as one contin-
uous vein. The little cross vein be-
tween the first and second transverse
nervures and the outer or upper branch
of the fork in the third transverse ner- vure are almost obsolete and scarcely
visible except in favorable light. Length of dry specimens one and one-half mrn.
Length of fresh specimens two mm.
The eggs (E) are a bright orange
color, .4 mm. in length and much elon-
gate. Some are straight, others are
variously bent and all are pointed at
one end and often with a short pedicel
attached.
This insect is decidedly an injurious
species. Trees upon the College cam-
pus that were the most severely attacked by this fly the past summer have had
not more than half of their normal
amount of foliage this year.
On the 18th of April, last, the writer
noticed the flies abundant among the
branches of the trees and the process of egg-laying was carefully watched with
a hand lens. The females were so in-
tent in their duties for the propagation of the species that they were not easily disturbed. They do not pierce the bud
scales but work their long slender ovi-
positors far down between the scales
and there deposit a large nest of eggs,
sometimes forty or more in a place. By
separating the scales the clusters of eggs can be plainly seen with the naked eye.
The irritation set up by these eggs and
the m.iggots that hatch from them aided, perhaps, by ii poisonous secretion from
the mother insect causes the abnormal
development of the part. The galls all
die a few weeks later when the maggots
leave them. These dead galls turn
black and remain upon the trees giving
them an unsightly appearance.
PREPARATORY STAGES OF CERURA MULTISCRIPTA, RILEY. BY HARRISON G. DYAR, RHINEBECK, N. Y.
Egg'. Slightly more than hemispher- leaf. These eggs had hatched when ical, the base flat, dead sordid white,
found, the larva having emerged from a
covered with many short dark brown
hole in the side, leaving the rest of the hairs irregularly laid on and distributed shell intact. also on the parts of the leaf adjoining. First stage. Head subquadrate, de-
Diameter 1.3 mm.
Laid in groups of
pressed at the vertex, black and shining. five or less on the under surface of a Width, .6 mm. Body furnished with



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minute tubercles, a spined process at
each side of the cervical shield and two tail-like appendages which take the place of the anal feet. Color bliick throughout a little paler ventrally.
Second stage. Head rounded, mi-
nutely punctured, with a tubercle below
the vertex of each lobe. Color purplish
black, a little paler about the sutures of the clypeus (triangular plate). A few
short hairs. Width .g mm. The body
has several rows of minute piliferous tu- bercles, two large, thick, heavilj s p' inose cervicle horns on joint 2 ; tails, long, sharply spinose, shiny black, the exten- sile threads purple black, whitish at base. Body velvety purple black, the venter
greenish. ~en~th of body 4 mm., of
tails 4 mm.
Third stage. Head with two tuber-
cles before the apex of each lobe, one in the centre of and one each side of the
clypeus. Color, dull black, clypeus and
mouth reddish, ocelli black, antennae
pale. Width 1.3 mm. Cervical horns
thick, heavily spinose, the spines blunt and each tipped with a hair. About
six rows of elongated piliferous tubercles on each side, alternating anteriorly and posteriorly on each segment. Tails long, heavily spinose, black, the extensile
threads brown, white at base. Body
and legs greenish yellow, a black dorsal band covering the cervical horns, nar-
rowing to joint 4 where the dorsum is
angularly elevated, widening to near the spiracles on joints 8 and 9, then contin- uing evenly over the subdorsal space to
the last segment. Spiracles narrowly
black ringed.
Length of tails, 5 mm.
Fourth stage. Head dead purple
black, greenish at the sides posteriorly, the upper half sprinkled with little yel- lowish dots, but leaving a line of the
ground color each side of the central su- ture.
\
Clypeus and mouth, paler and shiny :
antennae whitish, ocelli black. Width
2. I mm. Body as before, considerably
elevated dorsally at joint 4 with a round- ed pinkish dorsal process. Cervical
shield large, purplish black, the horns
rather thick and short, heavily tubercu- lated. Body yellow-green, the dorsal
stripe black as before, but a little pur- plish, spiracles white with a fine black border, the posterior ones more or less
surrounded by black. Tails heavily
spinose, black ; length 7 mm. The
piliferous tubercles of the body are very small, those on the lateral region white besides many small lateral white spots.
A narrow yellowish stigmata1 line.
Two erect spiny black hairs beyond
the anus.
As the stage advances, the spines on
joint 2 become partly white, the dorsal
band partly striated and indistinctly bor- dered anteriorly with white, the stig-
matal line just below the spiracles is
white and there is a general approach to the next stage.
F~yth stage. Head rounded, rather
flat in front, shagreened. Color black,
green at the sides posteriorly, a large
band in front as wide as the space be-
tween the eyes at base, but narrowing
to the vertex, sordid white, mo tied a
little with the ground color. Labrum
whitish ; maxillae black ; antennae




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August-October 1890.1 T^~ckl&. 393
white. Width of head 3.7 mm. Cer-
vical shield large, angulated at the
corners without any horns or spines.
Beneath it the head can be partly re-
tracted. Body angularly elevated at
joint 4 with a dorsal fleshy process.
Tails g mm. long, whitish above and
green below at the base, the rest purple with black spines. Extensile threads
at base, then red fading to
yellowish again towards the ends.
Body green, a broad white dorsal band
edged with white, confusedly striated
on a purple ground which soon be-
comes green, a little purple on joints
2-4, decidedly so on the anterior cor-
ners of the cervical shield (where it
shades into pinkish in the fold of skin
behind the head) on the 1111inp 011 joint 4 and 011 joint 8 subdorsally in the angle of the band. It begins broadly on joint
2 covering the cervical shield, narrows
to the process on joint 4. widens to just above the spiracles on joint 8 and grad- ually
narrows to joint 13, where the
anal plate is greenish. A distinct
white substigmata1 line, edged below
with brown and narrowly above with
black, absent on joint 2 and turned up
at its anterior end. Many small lateral
white flecks. Spiracles, black, white
centrally. Thoracic feet twice lined
with black longitudingly ; abdominal,
once transversely, the claspers tipped
with black. Length 25 mm. exclusive
of the tails. The erect spines beyond
the anus, whitish.
When the larva has
finished eating, all the whit^ of the
dorsal band except its borders fades
out, leaving the back green and the
cervical shield pale blue.
Cocoon. Formed on wood of gummy
silk strengthened by many little pieces
of bark and wood bitten off from the
inside, thus forming a hollow. It is
elliptical, just large enough to contain the larva and becomes very hard, closely resembling a lump or excresence on
the bark.
Pupa. Cylindrical, tapering a lit-
tle towards both ends, the last two
abdominal segments rounded and ap-
pressed, the others capable of motion ;
no cremaster. Eyes prominent ; a
narrow carinated ridge runs along the
head from between the eyes to the back
of the place of origin of the antennae.
Cases creased and very minutely punc-
tured, not shiny ; eyes and body sub-
lustrous, the latter minutely granulated at the anterior half of each abdominal
segment ; spiracles distinct. Color
dark reddish brown, with a blackish
shade over the dorsum. Length 18
mm., greatest width 6.5 inm. Pupation
occurs in about two weeks after the
completion of the cocoon and the in-
sects remain in this stage throughout
the winter.
Food plants.
Willow ( SaZix) , Pop-
lar (Po$zdus). Larvae from Dutch-
ess Co., N. Y.




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