INSECT-GALLS OF THE VICINITY OF NEW YORK CITY 



33. Pine-Cone Oak Gall {Cynips strobilana Osten Sacken). — Consists of 

 many -wedge-shaped bodies, closely packed together, with their pointed bases 

 attached to a common center. Hard and corky with a single cell in each. They 

 break off readily when dry. On twigs of swamp white oak (Querciis platanoides). 

 Not common. 



34. Oak Pea Gall {Cynips pisum Fitch). — Globular, green and about the 

 size of a pea, which it resembles in general appearance. Surface finely netted 

 with fissures or cracks and intervening elevated points. Inside are two cavities 

 divided in the middle by a thin partition. On iipper and under sides of leaves 

 of white oak {Qncrcus alba). 



35. Oak Hedgehog Gall {Acraspis erinacei Walsh). — Rounded or oblong 



