756 BACTERIAL FLORA OP THE SYDNEY WATER SUPPLY, 



Bacterium II. 



The organism is a short motile rod with rounded ends and 

 measures 0-4 : 0-8-1 -2 /x; it is decolorised by Gram's method of 

 staining. On gelatine plate the colonies are round, white, and 

 moist glistening. When magnified they appear rounded, light 

 brown, granular, and smooth-edged. 



The gelatine-stab is filiform with a restricted, lobular, flat nail- 

 head. No gas is produced from glucose. The stroke on agar is 

 white, moist glistening and slightly iridescent ; it slowly widens 

 laterally and spreads out at the base ; the condensed water has 

 no film. Litmus-lactose-agar is not affected. Bouillon becomes 

 turbid and forms a sediment and a slight film. A slight indol 

 reaction was obtained; nitrates wei*e not reduced. Milk is not 

 coagulated, and the reaction is unaltered. On potato the growth 

 is irregular, slightly raised, pale buff in colour and with a fatty 

 appearance; the growth becomes buff and moist glistening. The 

 organism grows slowly at 37° C. 



This bacterium was separated by Eisner's method. Its in- 

 difference to milk and glucose places it among the typhoid group 

 of bacteria. Its nearest ally appears to be Bac. pinnatus, 

 Ravenal. It has many points of difference from Bad. typhi. 



Bacterium III. 



A small, oval, actively motile bacterium measures 3:06/x, 

 and is not stained by the Gram method. The colonies on gelatine 

 are circular, white, and moist glistening. When magnified the 

 surface colonies are seen to be rounded, brownish, and flocose in 

 structure; 24 hours later flocose wisps are seen extending radially 

 from an irregular dark centre into the finely granular marginal 

 portion; in another 24 hours the flocose wisps have become club- 

 shaped processes. The deep colonies are rounded or lenticular, 

 granular and opaque; the sub-surface colonies moruloid. The 

 stab in gelatine is filiform and tuberculate, with an irregular 

 lacerate raised and terraced nail-head. Gas is given off from 

 glucose. The colonies on agar are thin, spreading and almost 



