E. M. DoiDGE 73 



a favourable medium. The liquid became turbid and a decided whitish 

 pelUcle formed on the surface. 



Bunhayii's solution became only very sUghtly clouded ; no pellicle 

 and very little sediment. 



Cohri's solution. No growth. 

 ^~ UschinsJcy^s solution at first is only shghtly clouded but a thin tough 

 pellicle forms; this increases in size, remaining adherent to the sides 

 of the tube and becoming saccate and dipping below the surface of 

 the solution in the centre of the tube. This peUicle finally sinks to 

 the bottom and the hquid then becomes densely clouded and baryta 

 yellow to buff yellow in shade. There is a decided ring above the 

 liquid which becomes ochraceous tawny to cinnamon brown. 



Cabbage broth. There is not much clouding and only a small 

 amount of sediment. The pelhcle however is quite conspicuous, it 

 consists of vast numbers of minute, opaque, yellowish bodies and 

 presents a frosted appearance. 



Lemon juice filtered through a porcelain candle and undiluted 

 proved to be too acid a medium for growth. 



Nitrate broth is heavily clouded but no pellicle forms owing to the 

 vigorous evolution of gas. The broth is covered with froth to the depth 

 of 1 cm., for some days. 



Physical and Biochemical Features. 

 Enzyme production. 



Proteolytic enzymes. Milk serum cultures tested at the end of five 

 days gave only negative results; after 10 days however, although 

 the culture gave negative reactions for proteose and peptone there 

 was a faint but immistakable reaction for tp-osin which was absent 

 in tests made from the control flask. 



Diastase. Potato cyhnders on which the organism had been grown 

 gave a distinct red brown reaction with iodine indicating the presence 

 of amylodextrin. The same reaction was observed in peptone water 

 containing potato starch, but in neither case was there anv reaction 

 for sugar with Fehhng's solution. 



Nutrient bouillon cultures to which were added 2 per cent, thymo 

 and equal quantities of starch paste did not precipitate Fehling's 

 solution after six to eight hours. 



Invertase was also absent from broth cultures. 



