KEY TO AMERICAN INSECT GALLS 



191 



Grindelia (gum-plant, tar-weed) 



Oval, blister leaf gall, greenish or blackish, diameter 3 to 4 mm, on G. r o b u s t a, 

 G. cuneifolia. Fig. 212. Felt 'i2e, p. 149; 'i6f, p. 180 



Itonid. Tar- weed blister midge, Asteromyia grindeliae 



Felt 



Reared from apparently unmodified flower heads. Fig. 213. Felt 'i6f, p. 186 



Itonid. Tar-weed blossom midge, Rhopalomyia grindeliae 



Felt 



Gutierrezia sarothrae 



Oval, flower bud gall, length 7 mm. Felt '151, p. 274 



Itonid. Gutierrezia bud midge, Rhopalomyia gutierreziae 



Ckll. 

 Slight enlargement of the slender stems, composed of blackened tissue, length 

 6 to 8 mm, diameter i mm. Fig. 214. Felt 'i6f, p. 179 



Itonid. Black gouty gall, Asteromyia gutierreziae Felt 



Fig. 215. Downy flower 

 gall, Rhopalomyia 

 anthophila O. S. 

 Cluster of galls. (Original) 



Fig. 216. Nun 

 midge, A s p h o n - 

 dylia monacha 

 O. S. Apical bud 

 gall. (Original) 



Fig. 217. Clarke's 

 goldenrod gall, 



Rhopalomyia 

 c 1 a r k e i Felt. 



(Original) 



Chrysopsis (golden aster) 



Woolly, polythalamous bud gall, diameter 1.5 cm. Felt '151, p. 278 



Itonid. Golden aster bud midge, Rhopalomyia chrysopsidis 



Lw. 

 Solidago (goldenrod) 

 Flower galls 

 Greenish or reddish, subglobular, budlike galls, diameter 2 mm, on S. 

 canadensis. PI. 12, fig. 6. Felt '151, p. 249 



Itonid Beaked flower gall, Rhopalomyia racemicola 



O. S. 

 Green, denselv pubescent, cylindrical gall, length 6 mm, on vS. canadensis. 

 Fig. 215, p' 12, fig. 5. Felt '151, p. 251 



Itonid. Downy flower gall, Rhopalomyia anthophila O. S. 

 Reared from undescribed flower gall. Felt '151, p. 268 



Itonid. Rhopalomyia c r u z i a n a Felt 



