294 CHEN CHONG CHEN AND LEO F. RETTGEE 



The Voges and Proskauer method of distinguishing between 

 B. coli and B. aerogenes has proven even more satisfactory than 

 the methyl red test, in that it is simple in operation, and when 

 correctly carried out thoroughly constant in its results. When 

 used with precaution, the uric acid test also is of fundamental 

 importance in differentiating fecal coli from the soil aerogenes 

 type of bacteria. 



No definite correlation could be established by means of the 

 indol test. Neither did motility study prove to be of practical 

 value. 



Adonitol fermentation did not prove itself to be a satisfactory 

 method of differentiating fecal from non-fecal strains of B. 

 aerogenes. 



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Univ. Sci. Bui., 4. 

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 Bettencourt, A., and Borges, I. Recherches sur le B. coli, des vertebres 



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Science, N. S., 42, 71. 



