CLASSIFICATION OF THE COLON-CLOACAE GROUP 



273 



(37.5 per cent) are positive with dulcitol, 7 (43.7 per cent) with 

 glycerol, and 7 (43.7 per cent) with salicin. From tables 9 and 

 9a it is seen that salicin is the best correlated character. Of the 

 seven salicin positive strains, 6 (85.8 per cent) attack dulcitol and 

 5 (71.5 per cent) glycerol. The characteristics of this group 



TABLE 10 



Distribution of organisms from different sources among the various species and 



varieties 



therefore resemble the B. neapolitanus of MacConkey's varieties. 

 On the other hand, 7 (77.8 per cent) of the 9 salicin negative 

 strains are negative for glycerol while all failed to ferment dulcitol. 

 These are therefore the B. coscoroba of MacConkey's classification. 



RELATION OF SPECIES TO SOURCE 



Table 10 shows the distribution of the organisms from different 

 sources among the various species and varieties. Species or 

 varieties and habitat seem to be somewhat related. 



B. aerogenes and B. cloacae were obtained only from soil and 

 sewage and were not isolated from any of the animals tested. 

 B. cloacae constituted 49.7 per cent of the soil and 2.6 per cent 



THE JOURNAL OF BACTERIOLOGT, VOL. Ill, NO. 3 



