U. S. DEPARTMENT OF AGRICULTURE. 



BUREAU OF PLANT INDUSTRY— BULLETIN NO. 29. 



B. T. GALLOWAY, Chirf of Bureau. 



. THE EFFECT OF BLACK ROT ON TURNIPS: 



A SERIES OF PHOTOMICROGRAPHS, ACCOMPANIED BY 

 •AN EXPLANATORY TEXT. 



BY 



ERWIN ¥. SMITH. 

 Pathologist, Laboratory of Plant Pathology, 



VEGETABLE PATHOLOGICAL AND PHYSIOLOGICAL INVESTIGATIONS. 



Issued ' January 17, 1903. 



WASHINGTON: 



government printing office. 



1903. 



