Oct. 29, 19" Relation of Soil Temperature to Onion Smut 261 



It is hoped that the evidence here recorded may lead to the accumula- 

 tion of further field data bearing upon this particular problem by inves- 

 tigators in various places, especially in the southern States. It is also 

 believed that these results illustrate well the importance of more per- 

 sistent inquiry by the experimental method into the relation of environ- 

 mental factors to the occurrence of disease of plants in general. 



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LITERATURE CITED 

 BouYOUCOS, George J. 



1916. SOIL TEMPERATURES. Mich. Agr. Exp. Sta. Tech. Bui. 26, 133 p. 

 Chapman, George H. 



I910. NOTES ON THE OCCURRENCE OF FUNGOUS SPORES ON ONION SEED. MaSS. 



Agr. Exp. Sta. 22 Ann. Rpt., 1909, pt. i, p. 164-167. 

 Heald, Frederick D., and Woolman, H. M. 

 1915. BUNT OR STINKING SMUT OF WHEAT. Wash. Agr. Exp. Sta. Bui. 126, 



24 p., 5 fig. (in text and on pi.). 

 HuNGERFORD, Charles W., and Wade, A. E. 



1920. RELATION BETWEEN SOIL MOISTURE AND BUNT INFECTION IN WHEAT. 



(Abstract.) In Phytopathology, v. 10, no. i, p. 53. 

 Jones, L. R. 



1917. SOIL TEMPERATURES AS A FACTOR IN PHYTOPATHOLOGY. In Plant World, 



V. 20, no. 8, p. 229-237, 2 fig. Literature cited, p. 236-237. 

 Mally, F. W. 



1915. THE BERMUDA ONION. Tex. Dept. Agr. Bui. 46, 56 p. 

 MuNN, M. T. 

 1917. NECK-ROT DISEASE OF ONiONG. N. Y. State Agr. Exp. Sta. Bui. 437, p. 

 361-455, II pi. Bibliography, p. 4SO-455- 

 SiRRiNE, F. A., and Stewart, F. C. 



1900. EXPERIMENTS ON THE SULPHUR-LIME TREATMENT FOR ONION SMUT. N. Y. 



State Agr. Exp. Sta. Bui. 182, p. 145-172, i pi. 

 Sturgis, William C. 



1896. TRANSPLANTING, AS A PREVENTIVE OF SMUT UPON ONIONS. In Conn. 



Agr. Exp. Sta. 19th Ann. Rpt. 1895, p. 176-182, pi. i. 

 Thaxter, Roland. 

 1890. the "smut" OF ONIONS, (UROCYSTis cEPUOrAE FROST). In Conn. Agr. 

 Exp. Sta. Ann. Rpt. 1889, p. 129-154, pi. 1-2. 

 Ware, Benjamin P. 

 1870. EXPERIENCE OF A PRACTICAL FARMER. In 17th Ann. Rpt. Mass. Bd. 

 Agr. 1869, Appx., p. 1-16, 



