236 A GUM BACTERIUM FROM A EUCALYPT. 



Saccharose-peptone agar. — The stroke becomes broad, raised or 

 hemispherical in section, sometimes undulating, and slowly gravi- 

 tates. The culture is of the appearance and consistency of thin 

 starch paste. The luxuriance of the growth is in striking contrast 

 to the growth on nutrient agar. 



Potato. — The growth is dry and glistening, whitish or slightly 

 yellow and constricted. The colour deej)ens to cream or pale 

 buff, and the grov/th becomes raised. It is always meagre, and 

 does not spread over the surface of the medium. 



Bouillon. — The medium Ijecomes turbid, and a fine white, loose 

 sediment is deposited, while a slight film forms on the surface. 

 A faint indol reaction is obtained In nitrate-bouillon the 

 nitrate is not reduced. 



Milk. — The medium is unaltered. 



Saccharose-peptone fluid. — The medium becomes milk-white, and 

 at a later stage becomes brownish-yellow. The gum can be 

 readily precipitated by alcohol, and Fehling's solution is strongly 

 reduced. 



The nearest allied bacterium capable of forming slime from 

 saccharose appears to be Bact. gelatinosum hetoi, Glaser, which 

 forms dextran and alcohol, but no lactic acid. As the gum, 

 moreover, has only been obtained previously from Bac. levani- 

 fovinans the bacterium is evidently a new species, and therefore 

 I have named it, on account of its origin. Bacterium eucalypti. 



EXPLANATION OF PLATE XIL 



Film of culture on saccharose-peptone-agar, stained with carbol-violet. 



X 1000. 

 Flagella stained by the night-blue method ; bacteria grown on ordinary 



nutrient agar, x 1000. 

 Dome-shaped colonies on saccharose-gelatine plate, x \, 



I 



