LETTER OF TRANSMITTAL. 



WASHINGTON, September, 1891. 



SIR: I have the honor of presenting for publication the first volume of the pro- 

 posed work called "Illustrations of North American Grasses," which have been 

 issued as Bulletin No. 12, parts I and II; and it is proposed to follow this with a 

 second volume of plates and descriptions of the " Grasses of the Pacific Coast." 

 Respectfully, 



GEO. VASEY, 



Botanist. 

 Hon. J. M. RUSK, 



Secretary of Agriculture. 



