Cynips quercus verrucarum n. sp.
Quercus obtusiloba [stellata]. Post Oak.
Small, round, pubescent, wart-like excrescences on the underside of the leaves. Diameter about 0.08.
They occur in numbers on one leaf in the latter part of the summer ; when the leaf is dead, the wooly pubescence of these excrescences is pale ferruginous, but earlier in the season, it is I suppose, snow-white, as are similar excrescences on other oaks.
”- Baron Osten Sacken: (1861) On the Cynipidae of the North American Oaks and their Galls©
Reference: https://www.biodiversitylibrary.org/item/22852#page/81/mode/1up