LETTER OF TRANSMITTAL. 



U. S. Department of Agriculture, 

 Division of Vegetable Physiology and Pathology, 



Washington^ D. C, January 15^ 1901. 



Sir: I have the honor to transmit herewith the manuscript for a 

 bulletin by Dr. Erwin F. Smith, of this Division, on the cultural 

 characters of Pseudoinonas hyacintld^ Ps. campestris, Ps. pliaseoli^ and 

 Ps. stewarti — four one-flagellate yellow bacteria parasitic on plants. 

 The first is the cause of a serious disease of h3^acinths, described in 

 Bulletin No. 26 of this Division; the second is the cause of a mdely 

 distributed and destructive disease of cabbages, known as brown rot 

 and described from a practical standpoint in Farmers' Bulletin No. 68; 

 the third is the cause of a serious disease of beans, and the fourth is 

 believed to be the cause of a serious disease of sweet corn. The Bul- 

 letin also contains occasional references to Bacilliis amylovorus^ B. coli 

 and other bacterial organisms which were used for comparison. It is 

 the first exhaustive working over of an interesting group of plant 

 parasites, concerning which practically nothing was known in 1896 

 when Dr. Smith began his studies. The work described is of a purely 

 technical nature, but will be valuable to those in experiment stations 

 and elsewhere who are engaged in investigating the bacterial diseases 

 of plants. I respectfully recommend that the paper be published as 

 Bulletin No. 28 of this Division, 

 Respectfully, 



Albert F. Woods, 



Chief of Division. 



Hon. James Wilson, 



Secretary of AgrimiUure. 



