BY R. GREIG SMITH. 143 



feebly; fuchsin, and especially violet, stain well. Staining l)y 

 Gram's method is negative. No spores are formed. 



Kelation to oxygen, etc. — The bacterium does not grow anaero- 

 bically, and the optimum temperature is 28° C. 



;^% glucose-gelatine ■plate.- — The colonies are white glistening, 

 slightly raised and irregular. When magnified they are seen to 

 have a dark clouded, convoluted or areolate centre, and a finely 

 granular margin, w^ith a crenate structure near the smooth edge. 



Nutrient gelatine plate. — Whitish or cream-coloured, round, 

 raised, glistening colonies. When magnified the surface colonies 

 are finely granular, the subsurface colonies are coarsely granular, 

 and the deep colonies are rounded and opaque. 



Nutrient agar plate. — The colonies vary in colour from dirty 

 white to buff-white; they are rounded, flat and glistening; the 

 centre becomes depressed. When magnified the rounded colonies 

 are fineh'' granular, with large granules distributed chiefly 

 round tlie centre. The older surface colonies are coarsely granular, 

 with a puckered or wrinkled centre. In crowded plates the small, 

 round, coarsely granular colonies maytiave a marginal ring (halo). 

 The deep colonies are rounded or lenticular with large coarse 

 granules. 



Nutrient agar stroke. — The growth is cream-coloured at 37°, 

 yellowish-white at 22°, slightly raised, glistening, and has a 

 lobular margin. The condensed water carries a slight film. 



Neutral cane-agar stroke. — A luxuriant, almost transparent, 

 yellowish-white, raised, spreading growth is formed. It has a 

 gelatinous consistency, and the condensed water is slightly viscous. 



Neutral cane-gelatine stroke. — An ivory-white or yellowish-white 

 glistening, irregularly raised growth, with an irrregular serrated 

 margin, and gummy or gelatinous consistency is produced. The 

 culture slowly gravitates, and forms a thick gummy mass at the 

 base of the slope. Sometimes there is no apparent liquefaction 

 of the medium until the gravitated gummy mass is removed and 

 a pit revealed ; at other times the site of the stroke l^ecomes 

 furrowed by a partial liquefaction of the medium. 



