Euura salicis nodus, n. sp.

On S. longifolia [interior]

A mere gradual enlargement of a twig from 1/4 more than its norma] diameter up to twice its normal diameter, almost always without any abnormal roughness on the external bark, and always not confined to one side only of the twig. General color that of the twig. When cut into, Aug. 28, the interior of each gall is found to be pithy, and to contain 1 — 3 larvae in separate cells. Frequently, on a piece of a twig 6 inches long, 2, 3 or 4 of these galls are placed at irregular intervals. No appearance internally of any transverse plates or transverse fibres as in S. ovum and S. ovulum. Length .75 — 1.50 inch; diameter .10 — .2.5 inch. Described from 31 affected twigs. Abundant but very local. Very like the Cecidomyidous gall S. nodulus on the same willow, but is much larger, is polythalamous instead of monothalamous, and occurs near Rock Island, IL., in quite a different locality. Analogous willow-galls are made in Europe, not by a Euura, but by several small species of Nematus.

- 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