JUL 25 19/7 



Bulletin 



OF THE 



Illinois State Laboratory 



OF 



Natural History 



Urbana, Illinois, U. S. A. 



STEPHEN A. FORBES, Ph.D., L,L^.D., 

 Director 



Vol. XII. June, 1917 Article IV. 



THE ZYGOPTERA, OR DAMSEL-FL,IES, OF IL^LINOIS 



BY 



Philip Garman, Ph.D. 



