107 



inoculated therefrom were get away in the dark at room tt'iii|ieratures of 19° to 25° 

 C. (mostly 21° to 23°). The other two were j.ut into thr thcrnioi-tat at 34.o5° to 

 35.55° for the first 4 days and then at 32.45° to 34.45° C. 



Result: The check tuhes were feebly clouded on the tliird day. They were first 

 examined at tlie end of 72 hours, and probably clouding could not have been detected 

 more than 6 or S hours earlier. These two cultures passed through a normal devel- 

 opment. The other tubes were left in the thermostat 27 days, during all of which 

 time they remained perfectly clear. On the twenty-seventh day both were removed 

 to room temperatures and watched for 6 weeks, Init they never clouded. When 

 removed from the thermostat each tube still contained about r).5 c. c. of fluid. 



The following- inferences respecting /*s. hf/actnf/u' appeiir to ])e war- 

 ranted hv these experiments: 



(a) The organism will not grow on any medium at-iC^ C, and after 7 

 days exposure to this temperature it will not grow at any temperature. 

 Prol)ably a much shorter exposure to 40"^ C. would kill it. 



(])) The organism will not grow in un neutralized (acid) beef broth 

 at W' to 38° C, and consequently it is not likely that it will prove 

 pathogenic to warm-])looded animals. 



(c) The organism will not grow in strongl}^ alkaline beef broth at 

 35 to 36.35'^ C, and after 6 days' exposure to this temperature it 

 will not grow at any temperature. 



(d) The organism will not grow on sugar-beet cylinders at 3.5° to 

 36.3.5° C, and after 13 days' exposure to this temperature will not 

 develop at any temperature. 



(e) The organism will not grow in strongly alkaline beef broth at 

 31:. 15° to 35.58° C, and after 8 days' exposure to this temperature it 

 will not grow at an}^ temperature. 



(f) When inoculated ver}' copiousl}' from a young solid culture, the 

 organism grew scantily on yellow turnip at 33.35° to 34.1:5° C. 



(g) When inoculated very copiously from a young solid culture, 

 the organism grew very feebly on sugar l)eet at 34.15° to 35^ C. 



(h) Growth already well under wa}^ in strongly alkaline beef broth 

 and on yellow turnip was stopped at 34.15° to 35.55° C. 



(i) In 8 days the organism made no visible growth on steamed carrot 

 at 33.35^ to 35.45° C, but all of the germs were not killed. 



(k) In 8 days the organism made no visible growth on yellow turnip 

 at 33.35° to 35.55° C, but all of the germs were not killed. 



(1) In 27 days the organism made no growth in unneutralized (acid) 

 l)eef broth at 34.55° to 35.55° C, and all were dead before the twenty- 

 seventh day. 



/^s. stewarti refused to grow at 40° C, in UschinskA^'s solution and 

 in strongly alkaline beef broth (0 of Fuller's scale). It grows in the 

 thermostat at 36° to 37° C, on most media, but not so well as at room 

 temperatures of 24° to 25° C. Ps. campestris did not grow at 40° C. , 

 and grew not at all or very feebly at 37° to 38° C. — i. e., about as Ps. 

 hyacinthi grows at 34° to 35° C. 



