BY R. GREIG SMITH. 461 



Nitrate-bouillon. — Nitrates are not reduced. 



Milk. — The casein and the reaction are unaltered. 



Potato. — The growth is white, dry, greasy, irregularly spreading 

 and slightly pitted. The colour changes to a light stone or light 

 drab. 



This appears to be an ally of Bac. verticillatus, Raw, from 

 which it appears to differ in the mycelioid or stellate appearance 

 of young colonies in gelatine, the rapidity with which it forms 

 spores on potato (2 days), the absence of a film on bouillon, and 

 of a pellicle on the gelatine colonies, as well as in not changing 

 the reaction of milk and in not affecting the colour of the medium 

 in agar culture. 



Two yeasts were separated, one of them pink with round to 

 oval cells, the other a non-sporulating torula which forms in 

 glucose-yeast-water a clear medium, with a white sediment and 

 strong, thick pitted film. It may be Torula ii., Hansen. With 

 the exception of Bad. cerofaciens and Bad. gasoformans, no 

 gas was produced in lactose-gelatine by the organisms which have 

 been described. Since these would have produced gas in gelatine 

 in the absence of lactose, it may be said that none of these 

 organisms produce gas from lactose. 



Many of the bacteria in the Sydney water have points wherein 

 the)- differ from what are probably the same organisms found in 

 other parts of the world. Whether these differences are sufficient 

 to warrant the formation of a new species is a matter of opinion. 

 I consider the characters in which they differ to be practically 

 fixed, since the cultures were made from about the fourth crop, 

 and when the organism was diagnosed any difference from the 

 described type was verified by a culture taken from what would 

 be the sixth crop. For all practical purposes the types may be 

 taken as fixed, since any work with Sydney water, sewage, etc., 

 would be made upon cultures which had been grown in a similar 

 manner and for no longer a time. The bacteriologist generally 

 does not keep an unknown organism growing for several months 

 before making a diagnosis. The characters may alter slowly after 



