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NATURAL HISTORY, TORONTO REGION

 

the single cell. The galls are found usually in dense masses around the stem, and are thus pressed into a somewhat elongated and flattened shape.

Cynips (?) constricts, Stebbins. Host, Quercus velutina, Lam. This gall has the form of a sphere surmounted by a short cylindrical portion slightly constricted at the base. It originates from the mid-rib or a principal vein of the leaf.

Diastrophus cuscutaeformis, O.S. Host Rubus villosus, Ait. Many galls are clustered together around the stem of dewberry. Each consists of a small, hard, spherical mass surmounted by a rosette of minute filaments.

Diastrophus turgidus, Bassett. Host Rubus idaeus var. aculeatissimus, Hegel and Tiling. Irregular, pithy swellings surrounding the stem.

Diastrophus fusiformis, Ashmead. Host Potentilla monspeliensis var. norvegica (L.), Rydb. An elongated, fusiform swelling of the stem of this cinquefoil.

Dryophanta palustris, O.S. Hosts Quercus rubra, L., and Quercus velutina, Lam. One of our commonest Cynipid galls. Almost as soon as this gall emerges from the bud, the larval chamber separates from the remainder of the gall.

Holcaspis globulus, Fitch. Host Quercus alba, L., and Holcaspis mamma, Walsh. Host Quercus macrocarpa, Michx. The former species is a spherical gall produced at the nodes of the stem. The latter

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