S triticoides, n. sp.

On S cordata [eriocephala?]

A polythalamous, woody gall .70 — 1.23 inch long and .30 — -.37 inch in diameter, bearing a remote resem- blance to a head of wheat with the kernels elongated, naked, pointed and very protuberant, its general outline oval or elongate-oval, and formed by the swelling of a twig to 2 or 3 times its former diameter, the swelled portion being very much contracted longitudinally, so as to bring each kernel-like bud nearlv or quite into contact with the base of the one that precedes it in the same row. the whole number being arranged in 4 irregular rows. Besides the swelling of the twig itself, the origin of each bud is also swelled into a more or less large tubercle, inside which is excavated longitudinally a cylindrical, slightly ru- gose and moderately polished cell, .25 — .27 inch long and .06 inch wide, the bud itself being elongated to about .17 inch and deformed so as to become a beak- like, tubiliform continuation of the cell, without any suture on the inside inter- vening, moderately polished inside like the woody part of the cell, and without pubescence as at the interior tip of the cell of 8. cornu n. sp. Through a slit at the tip of this beak-like bud the maker of the gall escapes, while, as usual, the parasite that preys on the gall-maker bores through it laterally. Above the gall the twig generally shrivels to about J its natural diameter, but occa- sionally where there are only a few cells — say 7 or 8 instead of 15 or 16 — it is not very materially diminished in size.— Described from 3 dead and dry speci- mens. Very rare near Rock Island. Larva, pupa and iMA(iO are all unknown; but from the structure of this gall being so exactly like that of *S'. siliqua n. sp. '( and espe- cially aS. cornu n. sp., there can be no doubt that it is. like those two galls, the work of a Cecidomijia . Inside several of the cells I found cocoons similar to those of C. s. strohiloldes. &c.. but much longer in proportion to their diameter, and not glued to the walls of the cell as in S. siltqua and *S'. cornu, so that I was able after relaxing the gall to extract two of them entire. They measured when extracted .42 — .44 inch in length and .06 inch in diameter, thus occupying the entire length and breadth of the cell including the beak formed by the bud. In the bottom of many of these cells, where the beak-like bud was bored laterally, I found an empty cocoon very similar to that of a parasitic Proctotrupide which occurs in the imago state in November in the central cell of aS^. strohiloides O. S. ; and in these cells there was no Cecidomyidous cocoon, as is also sometimes the case in the cells of C. s. strohiloidea that are occupied by the above Proctotrupide.

S hordeoides n. sp

On S humilis

This gall has some resemblance to a beardless ear of four-rowed barley, and differs as follows from S. triticoides : — 1st. The twig on which the cells are placed is not materially enlarged and is of a uniform diameter throughout. ^Ind. The twig is abnormally shortened as in S. triticoides, but only so that the tip of each deformed bud touches or nearly touches the base of the one that succeeds it in the adjoining row. instead of the base of the one in the same row. 3rr7. The entire cells ai*e only .20 inch long, instead of .42 — .44 inch, and they extend only .05 inch, or \ of their entire length instead of 3-5ths of their entire length, into the woody origin of the bud, the deformed buds being not much elongated, but hollow and. as well as the woody part of the cell, polished internally. Ath. The woody origin of the buds is scarcely swelled and protuberant. — Described from one dead and dry specimen, 1.40 inch long and .10 inch in diameter. It contains 10 deformed buds, regularly arranged with no undeformed ones intervening, as is the case in the monothalamous gall S. cornu, when several of them grow near each other. As in some S. triticoides. the tip of the twig has completely shrivelled up and per- ished. Easily distinguished from the monothalamous, Tenthredinidous gall, S. gemma n. sp., which occurs on the same Willow, by there being no normal buds between the affected buds, and by the buds themselves not being abnormally swelled out laterally, and being hollow, not solid, inside. But for the fact of several of the deformed buds having been bored by minute parasites, I should never have suspected this specimen of being what it most undoubtedly is — a true Cecidomyidous gall ; and but for its strong homologies with S. triticoides. I should hesitate whether to consider it as a congeries of solitary galls, like aS'. cornu. or a true polythalamous gall, where the twig itself is swelled and deformed and converted into a gall, like S. triticoides. It must be very difficult of discovery, when it is recent and the cells are unbored by any parasites. Larva, pupa and imago unknown.

- BD Walsh: (1864) On the Insects, Coleopterous, Hymenopterous & Dipterous: Inhabiting the Galls of Certain Species of Willow. Pt 1st--Diptera^©

Reference: https://www.biodiversitylibrary.org/item/23810#page/618/mode/1up