INSECT GALLS 



differs from it only in ending in a short, tapering 

 point. 



Holcaspis bassetti, Gillette. Host Quercus ma- 

 crocarpa, Michx. Produced in clusters surrounding 

 the stem. When not deformed by crowding, the gall 

 is circular in outline at the base, but tapers to a dis- 

 tinct point. 



Philonix hirta, Bassett. Host Quercus macro- 

 carpa, Michx. A spherical gall originating from the 

 midrib of the leaf ; its surface is faceted in appear- 

 ance. 



Philonix nigra, Gillette. Host Quercus alba, L. 

 This species is also spherical in form, but the surface 

 is felty in appearance, due to a dense pubescence. 



Philonix erinacei, Beut. Host Quercus alba, L. 

 Usually ellipsoidal in shape, springing from the mid- 

 rib of the leaf. The surface is again in this case 

 faceted, and each facet terminates in a distinct tri- 

 chome. 



On the hills of High Park a few specimens of 

 Rosa blanda, Ait., are found. These plants act as 

 hosts for a number of species of the genus Rhodites. 

 Infesting the stems are found Rhodites multispinosus, 

 Gillette, Rhodites globuloides, Beut, Rhodites dichlo- 

 cerus, Harris, while from the root originates Rho- 

 dites radicum, O.S., and from the leaves are pro- 

 duced Rhodites bicolor, Harr., Rhodites lenticular is, 

 Bassett, Rhodites ignotus, O.S., Rhodites gracilis, 

 Ashm., and Rhodites nebulosus, Bassett. Near the 

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