LETTER OF TRANSMITTAL. 
U. S. Department of Agriculture, 
Bureau of Entomology, 
Washington, D. C, December 12, 1911. 
Sir: I have the honor to transmit herewith, for publication as 
Bulletin No. 108 of the Bureau of Entomology, a manuscript entitled 
"Leafhoppers Affecting Cereals, Grasses, and Forage Crops." 
This matter was prepared by Prof. Herbert Osborn, professor of 
zoology and entomology in the Ohio State University, the best known 
American authority on these insects. Prof. Osborn was a temporary 
agent of the Bureau of Entomology, and spent about fourteen months 
in the work, visiting, during the warm months, various parts of the 
United States, and studying these insects in the field, on the farms 
and ranches, under natural conditions. He was able to devote his 
whole time to this work during tins period owing to the fact that the 
board of trustees of the Ohio State University kindly granted him 
leave of absence for one year. We have, in this document, the first 
effort made in this country to determine the exact economic impor- 
tance of these insects, together with the best methods of controlling 
them. 
Respectfully, L. O. Howard, 
Entomologist and Chief of Bureau. 
Hon. James Wilson, 
Secretary of Agriculture. 
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