QUALITATIVE BACTERIOLOGICAL ANALYSIS. 119 



turbid ; after forty-eight hours the broth cleared and a deposit 

 formed at the bottom ; on shaking the tube, long thin spiral 

 threads rose up from the bottom. 



Milk. Unchanged after ten days incubation. 

 Litmus-whey. No acid produced. After ten days incuba- 

 tion at 37 C. the reaction was slightly alkaline. 

 Glucose-gelatine. No gas formation. 



Peptone and Salt Solution. After seven days incubation at 

 37 C., a marked indol reaction. 



Potato. At first only a thin glistening film, but after ten 

 days incubation at 37 C., a distinct yellow growth was 

 apparent. 



Staining' Reactions. Stained by Gram's method. 

 Microscopical Appearances. A twenty-four hours broth 

 culture showed short chains and masses of very small cocci. 

 NOTE. This organism seemed to be intermediate between the 

 streptococci and the staphylococci. In its growth on 

 potato and liquefaction of gelatine it resembled sta- 

 phylo-cocci. But the growth in broth, milk, and lit- 

 mus-whey, and the microscopical appearances showed that 

 the culture was also closely related to the Streptococcus 

 pyogenes. 



None of the cultures when injected into guinea-pigs produced 

 any effects, either constitutional or local. 



Staphylococcus P. 



Gelatine Plates. Large, white, opaque, circular colonies, which 

 later acquired a lemon-yellow colour, and slowly liquefied the 

 gelatine. 



Agar-slope. A thick white growth, which later acquired a 

 lemon-yellow colour. 



Broth. Diffuse growth, with a slight deposit at the bottom. 



Milk. Unchanged. 



Potato. A rather dry, light yellow growth. 



Litmus-whey. No acid produced. 



Peptone and Salt Solution. No indol produced. 



Glucose-gelatine. No gas formation. 



Gelatine-stab at 37 C. A diffused growth with a small 

 deposit. 



