Article beginning on page 392.
Psyche 5:392, 1888.

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A NEW CECIDOMYIID INFESTING BOX-ELDER (*undo aceroides) .' BY C. P. GILLETTE, AMES, IOWA.
CECIDOMYIA NEGUNDINIS n. sp.
Galls. - The galls (G) are produced
from terminal buds on all parts
of the tree. Each is made up of a num-
ber of transformed leaves and peti-
oles arranged in pairs in which the two
leaves are opposite. They are sub-
globular in outline and vary from less
than one half of an inch to nearly an
inch in diameter. The outer basal por-
tion of the gall is formed by an enor-
mous enlargement of the bases of the
petioles of two leaves which unite and
form a receptacle like the cup of an
acorn holding the inner portions of the
gall. In the central part of the gall,
the leaf blades may be entirely involved or their tips may be partially expanded. Gall-flies.-Females, dry specimens.
Eyes large, coal black and coarsely
granulated ; antennae one-half the
length of the insect, 13-jointed, first
joint globular, remaining joints cylin-
drical, second and third joints con-
tracted in the middle, pedicels of joints CECIDOMriA NEGUNWIS n. sp.
Adult female, 0, avipositor, E, eggs, G, gall. Fly and eggs greatly enlarged. gall slightly enlarged. Original.
short, about one-quarter the
length of the joints, all of the
joints moderately set with hairs
the longest of which nearly
equals the joints in length.
Thorax very dark brown,
opaque, and naked except two
rows of long gray hails in lon-
gitudinal grooves running from
collar to scutell~~m and similar
hairs at the sides of the thorax ;
scutellum of the same coloi as
the mesothorax and with a few
long gray hairs. Beneath the
wings it is yellowish. Dor-
sum dark brown, sides of
abdomen and venter light yel-
low ; abdomen sparsely set with
gray hairs above and below.
Ovi$ositor yellowish brow ti
and in specimens taken while
ovipositing. it is exserted one
I Read before the Iowa academy of science, c, September 1390.




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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-
tudimil 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-hiilf mm.
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 13th 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 maggots that hatch from them aided,
perhaps, by a 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.
Eyy. 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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