List of the Insect Fauna of the County. 141
it ripens in September or October, and the gall-flies emerge
in late autumn. Dryophanta scutellaris, Olivier, or
Fig. 34. Dryophanta scutellaris or D. folii
D. folii, Linne (Fig. 34) [agamous form of Spathegaster
Taschenbergi] .
Quercus Robur, L. Leaf.
This gall is almost spherical,
slightly depressed at the top
and bottom, glossy, smooth,
yellowish or reddish in colour,
and occurs mostly in numbers
on the under side of the leaf.
It is about the size of a tick
bean, and is single-celled, but
the larva-cell is very large
relatively to the size of the
gall. This peculiarity and its
much harder consistency dis-
tinguish it at once from the
previous species, of which it
is only about half the size,
and is much more gregarious
than D. scutellaris (folii). The
galls occur in summer, and are
mature in early autumn, but Fig. 35. Dryophanta divisa.