S ovulum n. sp.

On Salix humilis

Undistinguishable both internally and externally from S. ovum n. sp. But for the fact that the larvae differ in color, and that, of the five species of willow found near Rock Island, IL., this type of gall occurs only on S. humilis and S. cordata [eriocephala] — two willows which are, according to Mr. Bebb, very distinct — and never, as I have carefully observed, on S. discolor — which is on the same authority, very closely allied to S. humilis, the species on which S. ovulum is found — I should not suppose S. ovulum to be a distinct (phytophagic) species from S. ovum. Possibly, indeed, it may not be so and to determine doubts it is better to await the discovery of male female imago. Besides the three bushes of S. discolor mentioned above, (Proc. Ill, p. 589,) I have since discovered and examined closely several dozens. This gall was rare in 1864 — 5 and 1865 — 6, but common in 1863 — 4. Not local, but generally distributed. Described from 30 specimens.

- BD Walsh: (1866) On the Insects, Coleopterous, Hymenopterous & Dipterous: Inhabiting the Galls of Certain Species of Willow. Pt 2nd and last^©

Reference: https://www.biodiversitylibrary.org/page/3830881#page/264/mode/1up