AEROBIC SPORE-BEARING NON-PATHOGENIC BACTERIA 307 



Gelatin stab. Growth along line of inoculation with funnel- 

 shaped surface hquefaction. No scum formation. 



Broth. Turbidity. No scum. Medium eventually becomes 

 yellow. 



Peptone. Turbidity. No scum. 



Potato. Thick, mealy, bright yellow growth gradually be- 

 coming dark yellow. 



Litmus milk. No change in 24 hours then a gradual pep- 

 tonization with the production of a port-wine-colored fluid. 



Blood serum. Thick, dry, yellowish, moist growth becoming 

 pale to bright yellow. No liquefaction. 



Fermentation tubes. Glucose. SHght turbidity in bulb. No 

 scum. No growth in closed arm. Feeble acid production. 



Saccharose. Slight turbidity in bulb. No scum. No growth 

 in closed arm. Faint acid production. 



Lactose. Shght turbidity in bulb. No scum. No growth in 

 closed arm. Reaction alkaline. 



Therynal death point. Spores survived steaming in Arnold 

 sterihzer 30 minutes, but were killed by 1 hour exposure. With- 

 stood 19 pounds pressure in autoclave but were killed by 20 

 pounds pressure. 



Bacillus tumescens Zopf 1885 



This organism was described by Zopf in 1885 (Zopf, 1885). 

 A culture received from the Krai collection and another received 

 from the American Museum agree in their morphological, 

 developmental, tinctorial and cultural features all of which are 

 identical with those of Bacillus megatherium. (Figures 45, 46 

 and 47.) 



^Bacillus graveolens Gottheil 1901 



This organism was described in 1901 by Gottheil (1901) as a 

 new species. A culture from the Krai collection in Vienna has 

 all the cultural reactions of Bacillus megatherium. Morphologi- 

 cally it is about the same size, forms spores in the same way, is 

 Gram-positive, produces globular bodies on plain and glucose 

 agar and undergoes involution with the formation of shadow or 



