INFECTIONS OF THE DIGESTIVE TRACT 173 



characters of typical colon bacilli, especially the capacity 

 to ferment sugars. Just as in the case of the typhoid 

 and paratyphoid bacilli, it is evident that the bacilli 

 farthest removed from colon bacilli (the typhoid bacilli) 

 in their characters incite the severest form of the disease, 

 so in the case of the dysentery bacilli it is true that the 

 severest forms of disease are dependent on those bacteria 

 farthest removed from the colon bacilli in their biochem- 

 ical characteristics; namely, the Shiga bacilli. The 

 Shiga bacilli are the cause of the severe epidemics of 

 Japan and of Germany, but in the latter country bear 

 the name of Kruse. The Flexner bacilli are apparently 

 the cause of dysentery in young children much more 

 frequently than the Shiga bacilli. The two types of 

 bacilli are further distinguished by their agglutination 

 reactions and somewhat less sharply by their behavior 

 toward immune sera. 1 The Shiga and Flexner organisms, 

 however, taken together do not quite cover the entire 

 range of bacillary dysentery ; for, as Park and Hiss have 



1 It has been proposed to group these types of dysentery bacilli 

 under the name paradysentery. As it appears to have been 

 conclusively shown that the lesions caused by these bacteria are 

 identical with those caused by the Shiga bacilli, there is no reason 

 why the "paradysentery" bacilli should not be regarded as dysen- 

 tery bacilli equally with the Shiga organisms. To use the term 

 "paradysentery" on the ground that the bacilli so designated stand 

 between the Shiga bacilli and the B. coli group in cultural, fermen- 

 tative, and other characters does not seem appropriate, for there 

 are doubtless many bacteria intermediate between the Shiga and 

 colon organisms which do not cause dysentery. For the present 

 it seems best to employ the names " Flexner type " and " Park-Hiss 

 type" in referring to the organisms in question. Doubtless 

 subdivisions within these types will prove desirable from a bac- 

 teriological standpoint. 



