454 BACTERIOLOGY. 



THE STRONG TYPE OF ORGANISM. This type of 

 organism has many of the characters of the Harris type, 

 though it ferments only mannite, dextrose, and saccha- 

 rose. 



THE HARRIS TYPE OF ORGANISM. This type of 

 bacillus dysenterise was first encountered by Strong 

 while working in the Philippine Islands. It has since 

 been encountered quite frequently in the United States, 

 especially in the summer diarrhoeas in infants. This 

 organism ferments mannite as well as dextrose, maltose, 

 saccharose, and dextrin. 



It is only by careful observations of the reactions 

 with the different carbohydrates that it is possible by 

 culture methods to differentiate between these different 

 types of bacillus dysenterise, as has been shown by Hiss 1 

 and by others. 



THE AGGLUTIN ABILITY OF BACILLUS DYSENTERIC. 

 The study of the influence of the agglutinins in dys- 

 entery immune serum has also served to differentiate 

 between different types of bacillus dysenterise. Normal 

 serums, especially those of bovines and of goats, also 

 yield very instructive results. These variations in the 

 agglutinability of the several types of bacillus dysenterise, 

 especially in normal serums, were first pointed out by 

 Bergey, 2 and have since then been substantiated by 

 many other investigators (see especially Park and Hiss, 

 loc. tit.). 



The different types of bacillus dysenterise can easily 

 be distinguished by their relative aggluti liability, but in 

 order to do so animals must be rendered immune from 

 each variety and the serum of such animals employed 



* Hiss : Journal of Medical Research, vol. vlii., Dec., 1904. 



* Bergey : .Journal of Medical Research, 19U3, vol. v., p. 21. 



