226 BACTERIOLOGY. 



colonies, with irregular borders. They are a little denser 

 at the centre than at the periphery. When magnified, 

 the colonies present wrinkles or folds, which give to 

 them, in miniature, the appearance seen in the relief 

 maps which represent mountainous districts. These 

 colonies have sometimes the appearance of flattened 

 pellicles of glass-wool, and glisten with more or less 

 of a bronze color. 



On Agar-agae the colonies present nothing typical. 



Stab Cultures. — In stab cultures the growth is 

 mostly on the surface, there being only a very limited 

 development down the track made by the needle. The 

 surface growth has the same appearance in general as 

 that given for the colonies. 



Potato. — The growth on potato is usually described 

 as luxuriant but invisible, making its presence evident 

 only by the production of a slight increase of moisture 

 at the inoculated point, and by a limited resistance 

 offered to the needle when scraped across the track of 

 growth. 



Potato Gelatin. — The growth is similar to that 

 upon ordinary nutrient gelatin. 



Milk. — It does not cause coagulation when grown in 

 sterilized milk. 



It does not liquefy gelatin. 



It grows both with and without oxygen. 



It does not produce indol. 



In bouillon it causes a uniform clouding of the 

 medium and brings about a slightly acid reaction. 



It does not grow rapidly. 



It does not produce fermentation with liberation of gas. 



It does not form spores. The irregularities of stain- 

 ing so commonly seen in this organism have in some 



