INSECT-GALLS OF THE VICINITY OF NEW YORK CITY 



•cells. About ^ to i^ in. in diameter. On branches of the pin oak {Qiiercus 

 palnstris). Exceedingly common throughout the year. 



20. Oak Knot Gall (Andnctis punctatus Bass.). — Shape similar to the 

 preceding gall, bu.t without the horn-like protuberances. Sometimes found 

 singly, but often a number may be seen, in greater or less proximity, on the 

 same branch. On black jack oak (Quercus marylandica), scarlet oak {Qiierciis 

 ■coccinea) and rarely on scrub oak {Quercus nana). Common. 





~- ->v 





2 1. Oak Seed Gall {Andricus sevninaiov Harr.). — Composed of a woolly 

 substance and irregularly rounded. Inside are numerous bodies adher- 

 ing to the twig and resembling canary seeds. About i to i \ in. in diameter. 

 Pure white sonietimes tinged with red ; toward the middle of the summer it 

 asstimes a rusty brown color and gradually drops off the twig. On twigs of 

 "white oak {Quercus alba). Common. 



22. Oak Wart Gall {Audncus jutiHs Osten Sackcn). — Rounded, somewhat 



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