COLON-AEROGENES FORMS FROM NATURAL WATERS 55 



Miss Bixby (1918) reports 6 strains from waters which are 

 methyl red and Voges-Proskauer positive; and 1 which is nega- 

 tive in both reactions. 



Levine (1918) included in the aerogenes-cloacae group all 

 strains which gave the Voges-Proskauer reaction, ''practically 

 always alkaline to methyl red," and 10 cultures which fermented 

 starch with gas formation but did not react typically for the 

 Voges-Proskauer nor the methyl red tests. Of the 151 organ- 

 isms 142 were from soil, 9 from sewage. 



Winslow and Cohen (1918) report perfect correlation between 

 the methyl red and Voges-Proskauer reactions for 53 strains in a 

 total of 54 isolated from polluted, unpolluted and stored water. 

 Winslow, Kligler and Rothberg (1919) speak of their series of 

 high ratio cultures as including 8 of the Bad. cloacae and 23 of 

 the Bad. aerogenes type, all but 1 alkaline to methyl red and 

 all but 8 Voges-Proskauer positive. 



Rettger and Chen (1919) report an "almost perfect correlation 

 between the two types" in the synthetic as well as in the Witte's 

 peptone medium (not in Difco) when the incubation period was 

 prolonged to five days. We have seen only the authors' abstract 

 of this paper. 



INTERPRETATION OF ADONITOL REACTIONS 



The adonitol positive reaction has been considered discrimina- 

 tive of Bad. aerogenes of fecal origin, and is so rated in the rather 

 diagrammatic scheme of the committee of the American Public 

 Health Association (1917). But Rogers (1918) considers that 

 while Bad. aerogenes isolated from feces is adonitol positive, it 

 does not necessarily follow that all waterborne Bad. aerogenes 

 with this character are therefore derived from immediate fecal 

 sources. 



Rogers, Clark and Lubs (1918) isolated aerogenes strains 

 from stools of but three out of eighteen persons; all of the 46 

 strains were adonitol positive ; but of the low ratio cultures from 

 similar sources 17 were likewise adonitol positive (12.98 per cent) . 



Darling (1919) cites numerous references in confirmation of 

 his findings: of 113 coli-like cultures isolated from feces of man 



