KEY TO AMERICAN INSECT GALLS 



123 



Bud-shaped, polythalamous twig gall without an opening. Fig. 117. Pack. 

 '90, p. 615 



Hemip. Hackberry bud gall, Pachypsylla gemma Ril. 



Fig. 119. Hop stem gall, Lasioptera humulicaulis Felt. 

 (Author's illustration) 



Conical, spine-shaped leaf gall on the under surface and arising from a circular, 

 yellowish base, height 4 mm, diameter 2.8 mm. Pack. '90, p. 614 



Itonid. Spiny hackberry gall, Cecidomyia spiniformis 



Patt. 



