194 Studies in Bacteriosis 



eventually after some three weeks a liquid basin is formed with a yellow 

 granular precipitate at the bottom. 



Stab culture on bouillon-gelatine +10, Growth was visible after 

 48 hours. On the third day there was no liquefaction, the margin of 

 the stab was echinate and that of the surface colony smooth and round. 

 There was still no liquefaction on the seventh day. The tubes were then 

 taken from the incubator and when examined a fortnight later lique- 

 faction had commenced at the top. Liquefaction was very slowly pro- 

 duced and even after six weeks only the upper portion of the stab had 

 become saccate. A granular yellow precipitate had collected at the 

 bottom of the liquid portion. 



Cultivation on other media. The organism grows well on media of 

 many plant extracts. Especially well on potato-mush-agar, on "Mar- 

 mite" (yeast extract) agar and in milk. Good growth was also obtained 

 on cabbage and celery agar. The most favourable reaction appears to 

 be about + 5 of Fuller's scale. The limits of tolerance towards alkali 

 were not determined. 



Streak culture on cooled potato. Growth was apparent after 24 hours. 

 On the second day the streak was 3 mm. wide, bright yellow, raised 

 and butyrous. No stain was produced in the surrounding potato 

 tissue. 



Thermal death point. Tubes of bouillon were immersed in a ther- 

 mostat at 45°, 47°, 49°, 51°, 53°, and 55° C. The hot broth was inoculated 

 with a loopful of a bouillon culture 24 hours old and left in the bath for 

 10 minutes at each temperature. On subsequent incubation those heated 

 above 51° C. failed to become turbid. 



C. Physiological Characters. 



For the following tests a 48-hours agar culture was used to inoculate 

 the tubes and the incubation temperature was 22° C. The strains isolated 

 independently by the two authors were set up in parallel and always 

 produced identical results. 



10 per cent, peptone -f 2 per cent, glucose. The colour of the litmus 

 became faintly red on the second day, a ring had formed and a loose 

 pellicle, but no gas. On the seventh day the acidity was not much more 

 marked, the colour was slightly redder than the control, no pellicle 

 formed but a decided ring; a very small bubble of gas had collected in 

 the Durham's tube, it had not a greater volume than that occupied by 

 the head of a match and later became almost entirely dissolved. The 

 colour remained practically of a neutral tint for some time and finally 



