356 LETHE E. MORRISON AND FRED W. TANNER 



Litmus milk. In this medium azolitmin was used as the indica- 

 tor. The litmus milk cultures were incubated at 55°C. for four 

 to seven days, only, because they evaporated so quickly at this 

 temperature. Peptonization occurred with at least 75 per cent 

 of the cultures; and in each of these cases the medium was alka- 

 line. All of the cultures curdled the milk and in those cases where 

 peptonization did not occur the medium was acid. More work 

 is being done on the growth of these organisms in milk and par- 

 ticularly on the use of brom-cresol purple as an indicator. 



Fermentation of sugars and glycerol. No gas was formed by 

 any of the cultures. None of the cultures produced acid in 

 lactose; the cultures varied slightly in their formation of acid in 

 glucose, sucrose and glycerol broth. Brom thjTnol blue was used 

 to test for acidity since that indicator was used to adjust the 

 reaction of all the broths when made. The amount of acid 

 formed in the different broths by these cultures may be of signifi- 

 cance and should be determined. 



Oxygen relation. This characteristic was determined by noting 

 the presence or absence of growth in the open and closed arm, 

 respectively, of fermentation tubes containing glucose broth. 

 All the cultures used in this study were found to be strict aerobes. 



Reduction of nitrates. To determine this characteristic, both 

 nitrate broth and nitrate agar slant cultures incubated at 55''C. 

 for four days were used. SulphaniUc acid and alphanaphthyl- 

 amine were used to test for nitrites. All of the cultures reduced 

 nitrates. 



Diastolic action on starch. Two per cent agar containing 0.2 

 per cent of soluble starch was used for this determination because 

 this stiffer agar seemed to stand the incubation at 55°C. better. 

 Dot inoculations were made in the center of the petri dishes con- 

 taining the hardened starch agar; these were incubated at 55°C. 

 for forty-eight hours since longer incubation dried the agar and 

 made it crack. All the cultures grew well on this media and all 

 produced diastatic action, some feeble and some strong. 



Temperature relations. Some of the cultures were grown on 

 agar slants at different temperatures and it was found that 50° to 

 55°C. was the optimum temperature for growth. Since it is 



