U. S. DEPARTMENT OF AGRICULTURE. 



BUREAU OF PLANT INDUSTRY— Circular No. 109. 

 B. T. GALLOWAY, Chief of Bureau. 



MISCELLANE( )US PAPERS. 



United States Official Cotton Grades N. A. COBB 



Potato Leaf-Roll • . W. A. ORTON 



Morphology of Cotton Branches 0. F. COOK 



The Wilting Coefficient for Plants in Alkali Soils T. H. KEARNEY 



Interpreting the Variation of Plat Yields F. D. FARRELL 



RK 



Issued January 4, 1913. 



WASHINGTON: 



GOVERNMENT PRINTING OFFICE. 



1913. 



