LETTER OF TRANSMITTAL 



U. S. Department of Agriculture, 



Bureau of Plant Industry, 



Office of the Chief, 



Washington, D. 0., April 15, 1912. 



Sir: I have the honor to transmit herewith and to recommend 

 for publication as Bulletin No. 252 of the series of this Bureau the 

 accompanying manuscript entitled "Studies of Fungous Parasites 

 Belonging to the Genus Glomerella," by Dr. C. L. Shear, Pathologist 

 in Charge of Grape and Small-Fruit Diseases, and Mrs. Anna K. 

 Wood, formerly Scientific Assistant in the Office of Fruit-Disease 

 Investigations. This paper has been submitted by Mr. M. B. Waite, 

 Pathologist in Charge of the Office of Fruit-Disease Investigations. 



This bulletin gives the results of studies of a group of fungous 

 parasites of great economic importance. Few fruits are free from 

 the attacks of this fungus. The life histories and relationships as 

 well as the physiological and pathological characteristics of the 

 organism from 36 different host plants are herein recorded, in many 

 cases for the first time. It has been found that what had heretofore 

 been regarded as distinct species of fungi restricted to certain host 

 plants are in reality merely races or strains of one species which is 

 capable of infecting various hosts. 



These facts have a very direct and important bearing upon 

 the practical problems of the prevention and control of the wide- 

 spread and serious diseases caused by these parasites and also upon 

 the broader general biological questions connected with the evolution 

 of plant parasites. 



Respectfully, B. T. Galloway, 



Chief of Bureau. 



Hon. James Wilson, 



Secretary of Agriculture. 



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