LETTER OF TRANSMITTAL. 
U.S. DeparTMENT OF AGRICULTURE, 
DIVISION OF AGrosroLocr, 
Washington, D. C., January 12, 1900. 
Sir: I transmit herewith and recommend for publi- 
‘ cation descriptions and analytical keys of the tribes 
and genera of North American Grasses. Each genus 
is illustrated, and reference is made to all other species 
of the genus illustrated in Bulletins Nos. 7 and 17 of 
this Division. There is added a bibliography of all the 
authors cited in these bulletins. This bibliography will 
be of great assistance to the working student, and the 
analytical keys will be helpful in identifying our Amer- 
ican Grasses. 
A portion of the matter here offered was published 
in the introduction to Bulletin No. 7, and although it 
may still serve as an introduction to the study of Amer- 
ican Grasses it has been deemed best to issue it in its 
present expanded form as a separate publication. It 
is in a measure complete in itself, and will be as useful 
to those who have already received Bulletins Nos. 7 
and 17 as to those who may receive copies of future 
editions of American Grasses, Illustrated. 
Respectfully, 
F. Lamson-Scripyer, 
Agrostologist. 
Hon. James WILson, 
Secretary of Agriculture. 
