Benj. D. Walsh on Insects inhabiting Willow Galls. 223 On the Insects, COLEOPTEROUS, HYMEITOPTEROUS and DIPTEROUS, in-habiting the Galls of certain species of Willow. — Part 2d and last. BY BENJ. D. WALSH, M. A. DIPTERA.— Supplement. GALLMAKERS.— Genus CECIDOMYIA, Subgenus CECLDOMYIA. No. 3. Gall S. strobiliscus Walsh. — I described this gall from a single dried specimen found by Mr. Bebb on Salix rostrata in North Illinois. I have since found very numerous specimens of what for the present I regard as the same gall on S. discolor near Rock Island, 111. Of 23 gathered March 23d one was undistinguishable from the S. rostrata gall ; the rest had the tips of the external leaves (except at the tip of the gall) not angulated, but more or less rounded with a subobsolete midrib outside which terminated in a minute tooth or beak. In other respects they did not differ, and especially in the veins on the inside of the leaves being obsolete or subobsolete. The general outline of this gall was ovate lanceolate, rarely ovate ; length — re-jecting one stunted specimen, which however contained a larva — 1.05 — 1.G5 inch, diameter .57 — .72 inch. The stunted specimen was not porrect, but deflected at an angle with the axis of the twig, and I sub-sequently found a few others varying in the same way. In one gall I met with 2 or 3 of the same rchelimum eggs which occur so copiously in S. strobiloides 0. S., and May 26th I bred several Orchelimum larvae from these galls. The larva and pupa, as well as the pupal integument, are undis-tinguishable from those of S. strobiloides 0. S., but the cocoon is shorter, being only lg — 2 times as long as the larva, instead of 2z — 3 times as long : 2 larvae and 2 pupae examined April 9. Imago. Cecidomyia s. strobiliscus n. sp. — Differs from Gee. 8. strobiloides,W alsh, only in the % antenna) being 23 — 24-joiuted, (not 21 — 22-jointed,) with 1 or 3 of the terminal joints sessile and the right aud left antenna varying iu the same S in the number of joints; and in the origin of the anterior branch of the 3rd longitudinal wing-vein being usually pretty distinct. Hence it can scarcely be separated from Gee. s. rhodoides Walsh, though the galls are quite different. One % . eleven $ , bred April 30 — May 8. No. 4. Gall S. unaplialioides Walsh. — I found a single specimen
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