LETTER OF TRANSMITTAL 
U. S. Department of Agbighltube, 
Bureau of Entomology, 
Washington, P. ('.. April 12. 1911. 
Sir: I have the honor to transmit herewith tin 4 manuscript of a 
report of progress on the importation into the United States of the 
parasites of the gipsy moth and the brown-tail moth. To this has 
been added some consideration of previous and concurrent efforts to 
handle the parasites of destructive insects in a practical way. The 
work with the foreign parasites of the gipsy moth and the brown- 
tail moth lias been <roin^ on now for rather more than five years. 
I: promises excellent results, and the present seems the proper 
time to present to the people interested a somewhat detailed account 
of what has been done and of the present condition of the work. \ 
recommend that this manuscript be published as Bulletin No. 91 
of this bureau. 
Respectfully, I.. 0. Howard, 
I'lhttunnhujlst ami Chief of Bureau. 
I [on, James Wilson, 
Secretary of Agriculture. 
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