NATUKAL HISTOKY, TOKONTO KEGIOST 



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(?) constricta, 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 

 villosuSj 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, Eegel and Tiling. Irregular, 

 pithy swellings surrounding the stem. 



Diastrophus fusiformis, Ashmead. Host Poten- 

 tilla monspeliensis var. norvegica (L.), Kydb. An 

 elongated, fusiform swelling of the stem of this 

 cinquefoil. 



Dryophanta palustris, O.S. Hosts Quercus ru- 

 bra, L., and Quercus velutina, Lam. One of our 

 commonest Cynipid galls. Almost as soon as this 

 gall emerges from the bud, the larval chamber separ- 

 ates from the remainder of the gall. 



Holcaspis globulus, Fitch. Host Quercus alba, L., 



and Holcaspis mamma, Walsh. Host Quercus ma- 



crocarpa, Michx. The former species is a spherical 



gall produced at the nodes of the stem. The latter 



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