U. S. DEPARTMENT OF AGRICULTURE. 



BUREAU OF PLANT INDUSTRY— BULLETIN NO. 139. 



B. T. GALLOWAY, Chief of Bureau. 



AMERICAN MEDICINAL BARKS. 



ALICE HEXKEL, 



Assistant, Drug-Plant Investigations. 



Issued June 5. 1909. 



WASHINGTON: 



GOVERNMENT PRINTING OFFICE, 

 1909. 



