AN INTRODUCTION TO 



BACTERIAL DISEASES 

 OF PLANTS 



BY 



ERWIN F. SMITH 



In Charge of Laboratory of Plant Pathology, 



Bureau of Plant Industry, 

 United States Department of Agriculture, Washington, D. C. 



Member of the National Academy of Sciences and of the American Academy of 

 Arts and Sciences; Fellow of the American Philosophical Society; Ex-President: 

 Society for Plant Morphology and Physiology (1901), Society of American 

 Bacteriologists (1906), Botanical Society of America (1910), American Phyto- 

 pathological Society (1917), etc. 



Ecrire I'histoire d'une science no-uuelle, c'est se vouer 

 a d'eternels recommencements. Madame Duclaux 



PHILADELPHIA AND LONDON 



W. B. SAUNDERS COMPANY 



1920 



