30 



19. Heald, F. 1). and Gardner, M. W. Longevity of pycno- 

 spores of the chestnut-blight fungus in soil. Journ. Agr. Re- 

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20. Heald, F. D., Gardner, M. W., and Studhalter, R. A. 

 Air and wind dissemination of the chestnut blight fungus. 

 Journ. Agr. Research 3 : 493-526. 1915. 



21. Heald, F. D. and Studhalter, R. A. Birds as carriers 

 of the chestnut blight fungus. Journ. Agr. Research 2: 405- 

 422. 1914. Preliminary note in Science N. S. 38: 278-280, 1913. 



22. Hodson, E. R. Extent and importance of the chestnut 

 bark disease. Unnumbered Cir. U. S. Dept. Agr., Forest 

 Service: 1-8. 1908. 



23. Tstvanffy, G. Ar Ithyphallus gomba es Coepophagus 

 atka egyiittes follepeser51 hazankban. Mathematikai es 

 termeszettudo-manyi ertesit^5 21: 157-176. 1903. 



24. Istvanffy, G. Ket uj sz()15k^rosit6 hazdnkban. A. m. k. 

 sz616szeti kiserleti dllom^s 6s ampelologiai intezet k(5zle- 

 menyei3: 1-54. 1903. 



25. Home, W. T., Parker, W. B., and Daines, L. L. The 

 method of spreading of the olive knot disease. Pythopathology 

 2: 101-105. 1912. Abstract in Phytopathology 2: 96. 1912. 



26. Johnson, E. O. Floret sterility of wheats in the south- 

 west. Phytopathology 1 : 18-27. 1911. 



27. Johnston, J. R. The history and cause of the coconut 

 bud-rot. Bui. U. S. Dept. Agr., Bur. Plant Ind. 228: 1-175. 

 1912. 



28. Jones, D. H. Bacterial blight of apple, pear, and quince 

 trees. Bui. Ontario Dept. Agr. 176: 1-64. 1909. 



29. Jones, D. H. Scolytus rugulosus as an agent in the 

 spread of bacterial blight in pear trees. Phytopathology 1: 

 155-158. 1911. 



30. eTones, L. R., Giddings, N. J., and Lutman, B. F. In- 

 vestigations of the potato fungus Phytophthora infestans. Bui. 

 U. S. Dept. Agr., Bur. Plant Ind. 245: 1-100. 1912. 



31. Klebahn, H. Die wirtswechselden Rostpilze. 447 pp. 

 Gebriider Borntraeger, Berlin. 1904. 



32. Ludwig, F. Lehrbuch der niederen Kryptogamen. 672 

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