LITERATURE CITED 215 



varieties at two stages of maturity to sixteen physiologic forms of 

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Grevel, F. K m "Untersuchungen iiber das Vorhandensein biologischer Ras- 

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Hammarlund, C, "Zur Genetik, Biologie, und Physiologie einiger Erysiph- 

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Hansen, H. N., and R. E. Smith, "The mechanism of variation in imperfect 

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Harrington, J. B., "The effect of temperature on the expression of factors 

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Harter, L. L., and J. L. Weimer, "Some physiological variations in strains 

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Hey, A., "Beitrage zur Spezialisierung des Gerstenzwergrostes, Puccinia 

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Hoerner, G. R., "Biologic forms of Puccinia corojiata on oats," Phyto- 

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Holton, C. S., "The relation of physiologic specialization in Tilletia to re- 

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 pathology, 21: 687-694, 1931. 



Johnson, C. O., "An aberrant physiologic form of Puccinia triticina Erikss.," 

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Johnson, C. O., and E. B. Mains, "Studies on physiologic specialization in 

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Johnson, E. M., and W. D Valleau, "Cultural variations of Thielaviopsis 

 basicola," Phytopathology, 25:1011-1018, 1935. 



LaRue, C. D., "The results of selection within pure lines of Pestalozzia 

 guepini" Genetics, 7: 142-183, 1922. 



LaRue, C. D., and H. H. Bartlett, "A demonstration of numerous distinct 

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 Botany, 9: 79-92, 1922. 



Leach, J. G., "The parasitism of Colletotrichum lindemuthiammt" Minn. 

 Agr. Expt. Sta. Tech. Bull., 14: 39 pp. 1922. 



Leontan, L. H., "Physiological studies on the genus Phytophthora," Am. J. 

 Botany, 12: 444-498, 1925. 

 "The morphology and pathogenicity of some Phytophthora mutations," 



Phytopathology, 16:723-731, 1926. " 

 "Studies on the variability and dissociation in the genus Fusarium," 



Phytopathology, 19: 753-868, 1929. 

 "Attempts to induce 'mixochimaera' in Fusarium monilifonne;'' Phyto- 

 pathology, 20:895-901, 1930. 



Levine, M. N., "Biometrical studies on the variation of physiologic forms 

 of Puccinia graminis tritici and the effects of ecological factors on the 

 susceptibility of wheat varieties," Phytopathology, 18: 7-126, 1928. 



Mains, E. B., "Host specialization of barley rust, Puccinia anomala" Phyto- 

 pathology, 20: 875-882, 1930. 



