BY R. -GREIG SMITH. 457 



Bacterium palaeformans, n.sp. 



Shape, etc. — A rod-shaped bacterium with rounded ends, 

 measures - 5-0"6 : T5-2 p and occurs singly, in chains and threads. 

 It is actively motile and is stained by Grain's method. It does 

 not form spores. There is little growth at 37°. 



Agar plate. — The colonies are circular, pale buff, raised and 

 moist glistening. When magnified the structure appears finely 

 granular and the margin erose. The deep colonies are irregular, 

 brownish and rough. 



Agar stroke. — A narrow, primrose-coloured, moist glistening, 

 raised stroke spreads out sharply at the base, when the condensed 

 water has been reached, until the sides of the tube are touched, 

 thus giving the culture the appearance of a spade. The colour 

 slowly deepens to buff. The consistency is found to be thin when 

 the culture is touched with a needle. 



Gelatine plate. — The colonies are zonate, pale buff in colour, 

 and have sunk into the gelatine, which is slightly liquefied. 

 When magnified sixty-fold, the deep colonies are seen to be 

 circular, brownish and annular; the surface colonies are either 

 circular with a corrugated dark border or lacerate-erose with a 

 coarsely granular centre. 



Gelatine stab. — There is no growth in the depth of the medium. 

 The gelatine is liquefied in a crateriform and afterwards in a 

 stratiform manner. The scanty deposit is deep yellow and like 

 a crumpled film. 



Glucose-gelatine. — There is no gas produced. 



Milk. — The medium is not coagulated. 



Bouillon. — The medium becomes slowly turbid and there is 

 formed a thin, pale yellow film and a scanty, filamentous precipi- 

 tate. The indol reaction was not obtained. 



Nitrate-bouillon. — Nitrate is not reduced. 



Potato. — No growth was obtained either at 22° or 30° C. 



This appears to be a motile form of Bad. dormitator, Wright, 

 but perhaps its closest ally is Bad. croceum, from which it differs 

 in colour, luxuriance of growth, and character of the gelatine 



