Larger oak apple gall, A m p h i b (-> 1 i ]> s c o n f 1 u c n t u s Harr. 



1 Two galls on a small twig 



Scrub oak gall, A m p h i b o 1 i p s i 1 i c i f o I i a e Bass. 



2 Two twigs bearing the peculiar fusiform galls 



Poplar stem gall, A g r o m y z a a e n e i v c n t r i s Fall 



3 Several galls on twigs 



Willow gall midge, Rhabdojihaga salicis Shrank 



4 Gall with pupal skins protruding therefrom 



760 



