Bui. Ill, Bureau of Entomology, U. S. Dept. of Agriculture. 
Plate II. 
Fig. 1— Wingless Progeny of Winged Hop Aphides from Alternate Host. 
(Original.) 
Fig. 2.— Willows Along Edge of Hopyard, which were Erroneously Supposed 
to Harbor Hop Aphides. -Original.) 
THE HOP APHIS. 
