Plate P. 



1 . ■Maple Vein gall, Acer Saccharum. 



2. Aspen Tent gall, Populus tremuloides. 



3. Balm of Gilead pimple gall, Populus 



balsamifera. 



4. Elm-Pimple gall, Uliiins Americana. 



5. Aspen Ball gall, Populus tremuloides. 



6. Ked Elm Bud gall, Ulmus fulva. 



i 



