214 PHYSIOLOGIC SPECIALIZATION AND VARIATION 



Christiansen, J. J., and H. A. Rodenheiser, "Physiologic specialization and 



genetics of the smut fungi," Botan. Rev., 6: 389-425, 1940. 

 Christiansen, J. J., and E. C. Stakman, "Physiologic specialization and mu- 

 tation in Ustilago zeae" Phytopathology, 16: 979-999, 1926. 

 Ciferri, R., "Osservasioni sulla specializzazione dell Albugo ipomoeae-pan- 



duranae (Schw.) S\v., Nuov. giorn. ltd., 35: 112-134, 1928. 

 Cotter, R. U., and M. N. Levine, "Physiologic specialization in Puccinia 



graminis secalis," J. Agr. Research, 45:297-315, 1932. 

 Craic;ie, J. H., "The origin of physiologic races of rust fungi through hy- 

 bridization," Genetics of Pathogenic organisms, Am. Assoc. Adv. Sci., 



66-72, 1940. 

 Diedicke, H., "Uber den Zusammengehang zwischen Pleospora und Helmin- 



thosporium-artcn," Zentr. Bakt., Parasitenk., II Abt., 9: 317-329, 1902. 

 Dimock, A. W., "Studies of ascospore variants of Hypomyces ipomoeae," 



My col., 57:709-727, 1939. 

 Dodge, B. O., "Inheritance of the albinistic non-conidial character in inter- 

 specific hybrids in Neurospora," My col., 23: 1-50, 1931. 

 "Heterocarvotic vigor in Neurospora," Bull. Torrey Botan. Club, 69: 75- 



91, 1942. ' 

 Eriksson, J., "Uber die Specialisierung des Parasitismus bei den Getreiderost- 



pilzen," Ber. dent, botan. Ges., 12: 292-331, 1894. 

 Faris, J. A., "Physiologic specialization of Ustilago hordei" Phytopathology , 



1 4: 537-557, 1 924. 

 "Factors influencing infection of Hordeum sativum by Ustilago hordei" 



Am. J. Botany, 11: 189-214, 1924a. 

 Flor, H. H., "Heterothallism and hybridization in Tilletia tritici and T. 



levis" J. Agr. Research, 44: 49-58, 1932. 

 "Studies on physiologic specialization in Tilletia tritici and T. levis in the 



Pacific Northwest," /. Agr. Research, 41: 193-213, 1933. 

 Frenzel, H., "Beitrage zur Spezialisierung des Haferkronenrostes Puccinia 



coroiiifera, f. sp., avenae Kleb," Arb. biol. Reichs. Land-u. Forstw. Berlin- 



Dahlem, 18: 153-176, 1930. 

 Gaines, E. F., "New physiological forms of Tilletia levis and T. tritici,'"' 



Phytopathology, 18: 579-588, 1928. 

 Gaumann, E., "Beitrage zu einer Monographic der Gattung Peronospora 



Corda," Beitr. Kryptogainenflora, 5: 1-360, 1923. 

 Gilbert, E. AI., "Biologic forms of black knot," Phytopathology, 5:246-247, 



1913. 

 Goldschmidt, V., "Vererbungsversuche mit den biologischcn Arten der 



Antherenbrandes (Ustilago violacea Pers.)," Z. Botan., 21: 1-90, 192s. 

 Gordon, \V. L., "Effect of temperature on host reaction to physiologic forms 



of Puccinia graminis avenae Erikss. and Henn.," Sci. Agr., 11: 95-103, 



1930. 

 ' \ suulv of the relation of environment to the development of the 



uredinial and telial stages of the physiologic forms of Puccinia graminis 



avenae Erikss. and Henn.," Sci. Agr.. 14: 184-237, 1933. 

 Goulden, C. H., M. Newton, and A. AI. Brown, "The reaction of wheat 



