286 J. S. LAWRENCE AND W. W. FORD 



Gelatin stah. Uniform growth along entire line of inoculation 

 with a liquefaction also along entire line. The liquefaction be- 

 comes cup-shaped or sacculated with a surface scum. It is rapid 

 and frequently in two days the entire gelatin tube is liquefied. 



Gelatin colonies. Loosely filamentous colonies with dense, 

 central nuclei and spreading irregular margins, often very thin, 

 edges entire. Gelatin liquefied rapidly. 



Broth. Very turbid in 24 hours with no scum except occasion- 

 ally a slight ring growth. In two days a heavy friable scum is 

 produced which is entirely precipitated within a short time. 

 The medium gradually clears while a heavy flocculent precipi- 

 tate is deposited. 



Peptone. Very turbid in 24 hours. Scum appears usually 

 on the second day and is soon precipitated. It is like that pro- 

 duced in broth but is more friable. 



Potato. Thick, white, mealy growth in a few days becoming 

 yellowish or brown with a discoloration of the potato. This 

 brownish growth may become very moist and sHmy and is 

 occasionally measley but never vermiform. It never assumes an 

 appearance similar to that seen with cultures of Bacillus subtilis 

 or Bacillus vulgatus. 



Litmus milk. With the majority of cultures peptonization 

 begins immediately and progresses rapidly in three zones. Sur- 

 face zone is amber, middle zone violet, the lowest zone blue. 

 Peptonization continues until the entire milk tube is converted 

 into an amber fluid with a slight sediment. Milk does not coag- 

 ulate. With some cultures the three-zone appearance does not 

 show but the milk is gradually changed to a muddy gray-colored 

 fluid. Eventually, however, the same clear amber-colored fluid 

 is produced. 



Blood serum. Thick, white, dry, smooth growth. No lique- 

 faction. 



Fermentation tubes. Glucose. Abundant growth in bowl and 

 arm. Friable scum forms which is soon precipitated. Turbidity 

 gradually disappears and a flocculent precipitate is deposited. 

 Reaction highly acid. 



Saccharose. Abundant growth in bowl and arm. Filmy and 



