SPORE-FORMING ORGANISM FROM IOWA 



337 



Lactose broth. Growth in lactose broth (with Andrade's indicator) 

 always observed in Durham fermentation tubes was not as vigorous 

 as in the glucose phosphate or starch mediums above. After 24 hours 

 there was usually a distinct acidity in the open arm while the inner 

 tube often showed but little acidity, (usually in lower end) and a 

 small amount of gas. After 48 hours the entire medium becomes 

 distinctly acid and 5 to 30 per cent gas may be obtained. 



Inulin, sucrose and maltose broths were all fermented with acid 

 and gas production. In all cases acid is first formed in open arm. 

 Gas formation was particularly vigorous with inulin. It seems to 

 be a peculiarity of this organism that it attacks the complex carbo- 

 hydrates much more vigorously than the hexoses. 



TABLE 2 

 Growth in Clark and Lubs medium (48 hours, 37) 



FERMENTATION OF CARBOHYDRATES IN SOLID MEDIA 



Nutrient agar containing 1 per cent of the test carbohydrate 

 and Andrade's indicator were employed. Incubation was at 37C. 

 for 10 days. It was observed that the more complex test materials, 

 starch, inulin, dextrin and glycogen were particularly vigorously 

 fermented in 2 days (as indicated by the extent of disintegration of 

 the agar) and that after 4 to 10 days, the acidity usually disappeared 

 and the medium reverted to a distinct alkaline reaction. Dulcitol 

 alone was not decomposed. 



Carbohydrates were tested with the results indicated in table 3. 



VOGES PROSKAUER AND METHYL RED REACTION 



Tests for acetyl methyl carbinol and acidity to methyl red were 

 made on all strains in Clark and Lubs medium after incubation at 

 body temperature for 4 days. The Voges Proskauer reaction was 



