860 



A YELLOW RACE OF BACILLUS PSEUDARABINUS, 

 FROM THE QUINCE. 



By R. Greig Smith, D.Sc, Macleay Bacteriologist to the 



Society. 



Upon examining the bacterial flora of some branches of the 

 Quince, several bacteria were obtained. With one exception 

 these did not appear to be capable of forming slime on glucose- 

 gelatine, levulose-asparagine-tannin-agar, or upon saccharose - 

 potato-agar — three media which generally give indications of 

 slime-formation. The exception was a bacterium which, upon 

 the original plates, w^as in the great majority. It was an organ- 

 ism which upon certain media, e.g., saccharose-potato-agar, ap- 

 peared as cocco-bacteria, while in others, such as bouillon, it was 

 seen to be stouter and longer. Upon most media there was evi- 

 dence of slime-production, and especially was this the case with 

 levulose-asparagine-tannin-agar, upon which Bact. acacice pro- 

 duces so much slime. The colonies upon glucose-gelatine were 

 suggestive of Bac. pseudarabinus"^ which had been isolated from 

 the Sugar-Cane, but as the colonies had a buff tinge on gelatine 

 and a decided yellow colour on agar, it was probably not that 

 organism. An examination of the gum was necessary, however, 

 before anj^thing could be said definitely about it. 



The gum was prepared in the manner that I have frequently 

 described. Large plates of levulose-asparagine-tannin-agar were 

 smeared with a culture of the organism, and the slime which grew 

 upon the agar surfaces was removed and coagulated with alcohol. 

 The coagulum was treated with water, warmed to expel the 

 alcohol and then heated in the autoclave at a pressure of three 

 atmospheres. This effected a liquefaction of the gum and at the 



* These Proceedings, 1904, p. 453. 



