LETTER OF TRANSMITTAL. 
U. 8S. DEPARTMENT OF AGRICULTURE, 
BuREAU OF ENTOMOLOGY, 
Washington, D. C., March 15, 1906. 
Str: I have the honor to submit a manuscript entitled ‘*A Classifica- 
tion of the Mosquitoes of North and Middle America,” prepared by 
Mr. D. W. Coquillett, assistant entomologist. The Department so 
frequently receives requests for information concerning this subject 
from students of entomology, from physicians, and from persons 
engaged in sanitary work that the desirability of an explicit publica- 
tion on this subject is very obvious. I therefore urge that the manu- 
script be published as Technical Series, No. 11, of this Bureau. 
Respectfully, 
L. O. Howarp, 
Entomologist and Chief of Bureau. 
Hon. James WILson, 
Secretary of Agriculture. 
