ROSACEAE. Spiraea salicifolia.

Cecidomyia? lappa, n. s.

Terminal mass of brown or, when quite young, green, mossy in appearance, strongly resembling Rhodites rosae, but coarser. Each gall consists of an undeveloped bud, the leaves of which have the tips much elongated. The central cavity is enclosed by the overlapping leaves. Not rare. On meadow-sweet, Spiraea salicifolia.

- FA Stebbins: (1910) Insect galls of Springfield, Massachusetts, and vicinity^©

Reference: https://www.biodiversitylibrary.org/page/33538396#page/37/mode/1up