79 



TABLE XLII. SUMMARY OF TYPES OF COLON BACILLI ISOLATED FROM 



VARIOUS SOURCES 



of different origin, should we not expect a correlation of the sanitary sur- 

 vey with the type of colon bacillus encountered in a water? Reliable in- 

 formation on this matter would certainly be a great aid in the interpreta- 

 tion of water analyses. Winslow and Cohen studied the distribution of these 

 organisms in waters of known sanitary quality with this idea in mind and 

 concluded that there was no relation whatsoever between the incidence of 

 aerogenes bacilli and the sanitary quality of the source. Thus among 94 

 strains isolated from polluted waters, 80 from unpolluted, and 81 from 

 stored waters in the vicinity of New Haven, Connecticut, organisms giving 

 the V.-P. reaction were encountered in 24, 24, and 15 percent respectively. 

 They conclude that the "significance of the ratio of Bact. coli and Bact. 

 aerogenes groups in a sanitary examination of water seems somewhat 

 dubious." Their results are quite the reverse of those reported by other 

 investigators. 



Greenfield and Skorup conclude that there is a correlation between 

 the increased incidence of the Bact. coli strains and the sanitary survey 

 during dry weather. 



TABLE XLIII. RELATIVE NUMBER OF AEROGENES AND COLI TYPES IN 

 WOLF CREEK. (Rogers 1918) 



