Callirhytis rubida, new species

Host. — Quercus coccinea Muenchhausen. Quercus rubra Linnaeus.

Gall. — Cells in the thick brown bark at or just below surface of ground on stumps or trees. Abrupt local swellings are formed which may even surround small saplings, the number of contained cells somewhat evident externally. (Plate 36, fig. 31.)

Type locality.— Ravinia, Illinois. Galls collected October 22, 1916, and when cut open about half contained full-grown larvae and half living adults. Host oak not recorded. On May 19 a similar gall was found at Millers, Indiana, in the thick bark of a stump of Q coccinea, and a living fly was cut out, which agrees with the Ravinia specimen in structure, but measures onlv 2.5 mm. Galls found on Q. rubra at Plummer Island, Maryland, and cut open September 21, 1919, gave five adults, two pupae, and several full-grown larvae.

Callirhytis rubida

Quercus coccinea, velutina
"Root" galls
Abrupt local swellings on stem below ground with cells in the thick brown bark. In the fall.

[Photo caption]
On Q coccinea. Also on Q rubra. Galls cut open on Sept 21 contained full-grown larvae, pupae and adults (DC). An adult was cut out May 19 (IL).