BY K. GREIG SMITH. 447 



temperature. Milk is not coagulated, nitrate is not reduced, but 

 a trace of indol is formed in bouillon. 



Zimmermann describes the organism as forming a blue-grey 

 stroke on agar. 



Bacterium salmoneum, Dyar. 



The organism grows scantily in artificial media. On gelatine 

 plate the colonies are small, hemispherical, moist glistening, and 

 of a pale scarlet colour; when magnified the structure is seen to 

 be finely granular and the margin smooth. The deep colonies 

 are rounded and opaque. The stab in gelatine becomes filiform, 

 and bears a small, rounded and raised vermilion nail-head. On 

 potato there is practically no growth. Bouillon becomes turbid; 

 there is a precipitate and a light reddish-coloured film. No 

 indol is formed. On agar the stroke is narrow and restricted, at 

 first coral-pink, then becoming light orange, and ultimately 

 reddish-orange. The organisms are non-motile thin rods with 

 rounded or slightly pointed ends ; they stain irregularly, and 

 measure generally 0-4 : 2 p. Milk is not coagulated, and the 

 reaction is unchanged. Nitrates are reduced to nitrites. 



Bacterium janthinum, Zopf. 



When grown upon agar the organism forms a deep violet, 

 moist glistening, irregularly raised layer with a white margin 

 and smooth edge; the consistency is gelatinous. The colonies in 

 gelatine appear as very pale violet indefinite areas, the parent 

 colony having sent out into the gelatine processes which have 

 formed sub-colonies. Both the indefinite parent colony and the 

 older sub-colonies are beset with processes similar to those of 

 Bad. Zophii. The younger colonies have a moruloid centre, and 

 are surrounded by circular or irregular sub-colonies similar in 

 appearance to the colonies of Bad. pullulans. The stab in 

 gelatine scarcely grows in the deep; the film is violet-coloured 

 and spreads over the surface, sending down into the medium 

 hair-like processes which appear like a hanging veil. The 



