INSECTS INJURIOUS TO THE LOCUST. 101 
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from before backwards, with projections along each side like the teeth of a saw; re- 
maining a week in the pupa state within the leaf, about the middle of August it issues 
as a small flattened black beetle with the prothorax and wing-covers, 
except along their suture, tawny yellow. (Fitch & Harris.) 
Harris states that in Massachusetts these beetles may be observed the 
middle of June pairing and laying eggs on the leaves of thelocust tree. 
While this species of leaf-mining betle is meet with in the 
New England States and New York, by information received ? 
diate 4 : es aes - Fie. 42.—Lo- 
from Kentucky it is at times quite injurious to locust trees in oustieaapae 
that State, but can always be kept under by hand-picking. EY Ea 
9. SAY’S WEEVIL. 
Apion rostrum Say. 
Order COLEOPTERA; family CURCULIONID®. 
From June until September, eating numerous small round holes in the leaves, a lit- 
tle black weevil with a slender projecting beak, its thorax with close coarse punctures 
and an oval cr longitudinal indentation back of its center, and the 
furrows of its wing-covers with coarse punctures; its length 0.09, and 
to the end of the beak 0.12 inch. (Fitch.) 
Dr. Harris states that the grubs of this little weevil live 
in the pods of the common wild indigo bush (Baptisia tine- 
toria), devouring the seeds. He adds, ‘‘A smaller kind, some- | 
what like it, inhabits the pods and eats the seeds of the lo- ates 
cust-tree, or Robinia pseudacacia.” Fitch regards the insect ‘7 °°" 
as very variable, and as most probably destructive to the seeds of both 
the plants here mentioned. 
10. THE BLACK LOCUST MIDGE. 
Cecidomyia pseudacacie Fitch. 
Order DipTERA; family CECIDOMYIAD#. 
In July and August, the tender young leaflets near the tip of the stem folded together 
like a little pod, the cavity inside containing from one to three small milk-white mag- 
gots, which descend below the surface of the ground, remaining there in the pupa 
state about ten days, and then appearing as a small blackish midge. (Fitch.) 
According to Fitch, before the small young leaflets, which put forth 
along the opposite sides of the main leaf-stalks at their tips become ex- 
panded, they are closed together like two leaves of a book; and it is 
probably at this time that the female midge inserts her egg in the cleft 
between them, the irritation from which and from the small maggots 
which hatch from them, keeps the leaflet permanently closed; a slight 
cavity forming within, in which the worms reside, the leaflet hereby 
comes to resemble in its shape a small bivalve shell with a more or less 
wavy edge. The surface remains unchanged outside, but within it 
assumes a pale greenish yellow color. The attachment of the leaflets to 
the stalk becomes so weakened when infested by these worms that prob- 
