396 



MEaiANISM OF GRANULAR GROWTH 



experiments was identical with that described in the preceding paper 

 (5). 1 cc. of the buffer mixtures was added to equal volumes of four 

 times washed distilled water suspensions of Microbes D and G, 

 bacillus of rabbit septicemia. The mixtures were placed in the water 

 bath at 43°C. for 16 hours, and readings taken. The results of this 

 experiment are recorded in Table I. 



TABLE I. 



Agglutination of Microbes D and G in Na Lactate-Lactic Acid and Glycocoll-HCl 



Buffer Series. 



In this and the following tables the mixtures were kept in the water bath for 

 16 hours at 43°C. C indicates complete flocculation; Tr., trace. 



The results given in Table I indicate that other factors besides the 

 Ch+ are important in the interpretation of the acid agglutination 

 point of the organism in question. In the case of Microbe D, Na 

 lactate-lactic acid series, for example, complete flocculation occurs at 

 pH 3.5 to 3.3, slight at pH 3.0, a trace at pH 2.7, and none at all at 

 pH 2.4. 



On the other hand, Microbe D in the glycocoll-HCl series, floccu- 

 lates completely at pH 3.0, 2.8, 2.6, and 2.4. This difference of effect 

 in the two buffer series is illustrated graphically in Fig. 1 . 



A similar result occurs in the case of Microbe G which flocculates 

 completely at pH 4.7, 4.5, and 4.1, and not at all at pH 3.0 to 2.4, in 

 the Na lactate-lactic acid series. Yet ++ agglutination occurs at 



