CHAPTER XXV. 



The Group of Bacilli Found in Cases of Epidemic, Endemic, and Sporadic 

 Dysentery The Morphological, Biological, and Pathogenic Char- 

 acters of the Several Members of the Group The Differentiation of 

 the Different Types of Bacilli. 



BACILLUS DYSENTERIC. 



THE investigations of epidemic dysentery by Shiga, 

 Flexner, Kruse, Vedder, Duval, Basset, Park, and many 

 others, have demonstrated that this disease is caused by 

 an organism that varies somewhat in its characters as 

 encountered in different cases. So far at least four types of 

 organisms have been found that differ in minor particulars, 

 though not sufficiently to warrant their designation as 

 distinct species. The type of organism first encountered 

 by Shiga, in Japan, is the one that is probably very widely 

 distributed, because it has been found in practically every 

 place where search has been made for it. The type of 

 organism encountered by Flexner in the Philippine Islands, 

 and believed by him to differ from the Shiga type, has also 

 been found very generally in the United States, especially 

 in dysentery occurring in infants. The type of organism 

 isolated by Hiss and Russell, and later by Park and his 

 associates, has most of the characteristics of the Flexner 

 type of organism, though the agglutination reaction shows 

 that it is not identical with it. 



At first the German investigators were inclined to regard 

 the Flexner type of organism as having no causative relation 

 (514) 



