Callirhytis subcostata, new species

Host. — Quercus stellata.

Gall (pl, 16, fig. 10). — Produced on the side of the acorn cup when the latter is about 4 mm. in diameter and dropping off when mature in late May. Green, 2.5-3.0 mm. in diameter, ribbed like a melon with about 16 grooves, pinkish in the grooves.

Habitat. — The types emerged April 1, 1950, from galls collected at East Falls Church, Va., on May 29, 1949. The nutritive layer was then about used up and the galls about ready to drop. This isolated tree had been visited almost every spring for many years but these galls had never been seen there before.

Callirhytis subcostata

Quercus stellata
Acorn galls
Produced on side of acorn cup in May, green, ribbed like a melon, 2.5-3 mm in dia.

[Photo caption]
Q stellata. A ribbed gall 2.5 to 3 mm in dia, produced on the side of the acorn cup when the latter is about 4 mm in dia and dropping in mid June (DC). Adults emerged the next spring April 1.