Bulletin No. 16, New Series. 
U. S. DEPARTMENT OE AGRICULTURE, 
DIVISION OF ENTOMOLOGY 
THE HESSIAN FLY IX THE 
EXITED STATES. 
PREPARED UNDER THE DIRECTION OF THE ENTOMOLOGIST, 
By HERBERT OSBORN, 
Prof essor of Zoology and Entomology, Iowa Agricultural College, Ames, Iowa. 
WASHINGTON: 
GOVERNMENT PRINTING OFFICE, 
18 9 8. 
