LETTER OF TRANSMITTAL 
U. S. Department of Agriculture, 
Biological Survey, 
Washington, D. 0., July 10, 1906. 
Sir: I have the honor to transmit herewith, for publication as Bulle- 
tin No. 26 of the Biological Survey, a report on the Distribution and 
Migration of North American Ducks, Geese, and Swans, by Wells W. 
Cooke, assistant in the Biological Survey. Formerly abundant over 
the whole of the United States, waterfowl are steadily diminishing in 
numbers, and some species appear to be threatened with extinction in 
the not distant future. Their value for food is great, and they have 
formed in the past, and for all future time should continue to form, a 
valuable asset and an important source of revenue to the several States 
which harbor them. The preservation of the numerous species of 
ducks, geese, and swans is becoming an important matter of legisla- 
tive enactment, and the present report is intended to furnish informa- 
tion as to present range, abundance, and migration of the several 
species with reference to practical legislation. 
Respectfully, 
H. W. Henshaw, 
Acting Chief, Biological Survey, 
Hon. James Wilson, 
Si en in i'ij of Agriculture, 
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