GENUS BACTERIUM 233 



aniline dyes. It stains well in aqueous solutions of fuchsin, 

 methylene blue, Bismarck brown and night blue. It takes the 

 Grain stain. 



Cultivation. It grows readily on the ordinary culture 

 media. 



Agar. A luxuriant white opaque growth, with slightly 

 wavy margins, occurs along the line of inoculation. It attains 

 the maximum growth in about 24 hours. 



Gelatin. At 20 to 25 C. growth occurs both on the sur- 

 face and along the line of inoculation. Around the place of 

 entrance is a spreading, brownish, deeply dentated growth. 

 Along the needle track the growth appears as small, yellowish, 

 closely packed colonies. On gelatin plates in twenty-four 

 hours colonies l 1 /^ mm - i n diameter appear. The border is 

 raised on a level with the rest of the colony. There is a papil- 

 lated center. The colony has a yellowish color. The sub- 

 merged colonies are yellowish and have irregularly lobulated 

 margins with well-defined edges. 



Potato. On this medium in three days there occurs a yel- 

 lowish creamy growth, spreading around the base of the potato 

 cylinder. Along the line of inoculation gas-containing blisters 

 indicate its property of fermenting starch. Some of these have 

 burst, causing crater-like depressions in the growth. The odor 

 is pungent and disagreeable. 



Bouillon. The medium becomes densely turbid in 24 

 hours. A ring of deposit which is easily broken is found at 

 the surface of the liquid. The odor resembles that in cultures 

 of the swine plague organism. The reaction is slightly acid. 

 In acid bouillon, the organism flourishes well, causing a dense 

 turbidity with a floating pellicle and a ring of deposit around 

 the tube at the level of the liquid. The culture has a putre- 

 factive odor and is of a yellowish green color. On the third 

 day considerable white deposit occurs. In a 1% glucose 

 bouillon, fermentation begins the first day and is completed on 

 the third. The reaction becomes strongly acid. Growth occurs 

 throughout the tube. It has a sour odor. The gas formula is 



