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plates. In the plates of both oysters there came up blue 

 colonies of the following characters. 



Drigalski plate of oyster 1, from clean sea water, con- 

 tained three blue colonies, that is, 150 per oyster ; these 

 proved to be colonies of a motile rapidly liquefying vibrio, 

 in many respects similar to vibrio finkler. 



Drigalski plate of oyster 2, from polluted water, contained 

 crowds of beautifully blue colonies, slightly raised, homo- 

 geneous and watery. On microscopic examination the 

 majority proved to be motile vibrios, rapidly liquefying 

 gelatine like vibrio finkler. 



Drigalski plate of oyster 5, kept three days in clean 

 water, had no blue colonies. 



Drigalski plate of oyster 6, two days in polluted water, one 

 day in clean water, had two bright blue colonies. This would 

 make 100 per oyster. These were shown to be the same, viz., 

 small watery colonies as above, viz., vibrio, but non-liquefying, 

 and in sub-culture of the same characters as those mentioned 

 as occurring in the sewage. 



Oyster 4, having been kept for 48 hours in sewage 

 polluted sea water, when examined showed in a Drigalski 

 plate (prepared with ^ part of the oyster) two watery blue 

 colonies. This would amount to 100 per oyster. Sub- 

 cultures of both these blue colonies proved them to be of the 

 nature of the motile Bacillus streptoides described as isolated 

 from the sewage. 



From this experiment we learn, then, that an oyster not 

 placed in the sewage polluted water (oyster 1) contained a 

 liquefying vibrio (probably similar to vibrio finkler), the 

 same as oyster 2, which had been 24 hours in sewage polluted 

 water ; further, that in another oyster (6), which had been 

 48 hours in sewage polluted and one day afterwards in clean 

 water, we identified the non-liquefying vibrio isolated from 

 the sewage ; and in an oyster (4) which had been 48 hours in 

 sewage polluted water we isolated the motile B. streptoides, 

 the same as was found in the sewage. 



From these facts it appears, then, justifiable to conclude 

 that the oysters placed in sewage polluted water had imbibed 



