UNITED STATES DEPARTMENT OF A 



BULLETIN No. 



Contribution from the Bureau of Plant Industry 

 WM. A. TAYLOR, Chief 





Washington, D. C. 



PROFESSIONAL PAPER 



January 15, 1917 



ENDOTHIA PARASITICA AND RELATED SPECIES. 



By C. L. SHEAR, Pathologist, and NEIL E. STEVENS,* Pathologist, Fruit-Disease 

 Investigations, and RUBY J. TILLER, Scientific Assistant, Office of Investiga- 

 tions in Forest Pathology. 



CONTENTS. 



Distribution of the species of Endothia. . 



Discovery of Endothia parasitica in 

 China 



Discovery of Endothia parasitica in Japan 



Present distribution of Endothia para- 

 sitica in America 



Host relations of the species of Endothia . 



Page. 



48 



54 



58 



.39 

 BO 



74 

 77 



TAXONOMY. 



INTRODUCTION. 



The discovery of a serious canker of the chestnut in the New York 

 Zoological Park in 1904, by Merkel (49), 2 first attracted the atten- 

 tion of pathologists and foresters to what has proved to be one of 

 the most serious epidemics of a plant disease ever known in this 

 country. 



The fungus which was found associated with these cankers (PI. 

 I and PL II, fig. 1) and soon demonstrated experimentally to be 

 their cause was described by Murrill (57) in 1906 as a new species, 

 of Diaporthe (D. parasitica). Search for the fungus in other places 

 in New York and vicinity soon showed that it was already estab- 

 lished and apparently rapidly spreading. Investigations which 

 have been continued and extended from year to year have shown 



1 Formerly Pathologist, Office of Investigations in Forest Pathology. 



2 Serial numbers in parentheses refer to " Literature cited," at the end of the bulletin. 



NOTE. This bulletin is of value to botanists, especially plant pathologists and mycolo- 

 gists, and to all persons who are interested in the study of chestnut blight. 

 43737 Bull. 38017 1 



