LETFI-R OF TRAXSMriTAL 



U. S. Department of Agriculture, 



Bureau of Plant Industry, 



Office of the Chief, 



Washlngto7), I). C, Octoler /, 1902. 



Sir: I have the honor to tninsinit herewith a technical paper on 

 "The Effect of .Black Rot on Turnips: A Series of Photomicrographs, 

 Accompanied \y\ an Explanatory Text," and respectfully recommend 

 that it be published as No. 29 of the series of bulletins of this Bureau. 

 The paper was prepared b}' Dr. Erwin F. Smith, in charge of the 

 Laborator}^ of Plant Pathology, Vegetable Pathological and Physio- 

 logical Investigations, and was submitted b}" the Pathologist and 

 Physiologist. 



Respectfully, 



B. T. Galloway, 



Chief of Bureait. 

 Hon. James Wilson, 



Secretary of Agriculture. 



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