6 



SMITHSONIAN INSTITUTION 

 UNITED STATES NATIONAL MUSEUM 



CONTRIBUTIONS 



FROM THE 



United States National Herbarium 



Volume 21 ; 



FLORA OF THE DISTRICT OF COLUMBIA 



AND VICINITY 



By A. S. HITCHCOCK and PAUL C. STANDLEY 



"WITH THK ASSISTANCE OF THE BOTANISTS 

 OF WASHINGTON 



WASHINGTON 

 GOVERNMENT PRINTING OFFICE 



1919 



