On leaf, generally upper side, delicate, small, sub-cylindric galls,
standing erect, 2-2½ mm. high, less than 1 mm. wide, constricted
proximally to the slightly flaring base. Distal end marked off by a
circular ridge, in the center of which is a rounded nipple. This latter
turns dark early. Gall light green, at length turning brown. Arises
from intervenal areas between the smaller veins. On the under side of
the leaf the gall above is indicated by a minute dark area. Attached to
leaf by minute central pedicel.
Collected in Hocking County, Ohio, on _H. alba_ in July.
Type specimens at Ohio State University.