KEY TO AMERICAN INSECT GALLS 



6i 



g Pustular elevations of the bark, often enlarging the twig 

 Abrupt, irregular twig swellings varying from round, pustule-like bodies 4 mm 

 in diameter to confluent, polythalamous masses 25 mm long and 12 mm in 

 diameter, on Q. p r i n u s. Fig. 107, 11. Beutm. 'loc, p. 120 



Cynipid. Neuroterus rileyi Bass. 



h Monothalamous terminal enlargements or club galls on twigs 

 Globe-shaped, apical, woody twig galls, length 12 to 25 mm, on Q. alba. 

 Fig. 58, pi. 2, fig. 2. Osten Sacken '65, p. 351 



Cynipid. White oak club gall, Andricus clavulus O. S. 



Fig. 59. Andricus gemmarius Ashm. 

 Badly infested twig and one gall enlarged. 

 (Original) 



Ovate or globose apical twig gall, leafy, diameter 7 to 8 mm, on willow oak. 

 O. S. '61, p. 70 



Cynipid. Andricus^ p h e 1 1 o s (). S. 



1 Generic reference by Beutenmuller. 



