342 MICROBIOLOGY 



grain and forage plants and in other localities. As it seems 

 to be widely distributed, their suggestion is that the occur- 

 rence of the disease depends upon the presence of pathogenic 

 races of the organism. The following description is taken 

 from their exhaustive article which contains an extensive 

 literature on milk sickness. 



Morphology. In cover-glass preparations from the or- 

 gans the bacilli are longer and more slender than the colon 

 bacilli, and occasionally stain unevenly with methylene blue. 

 In preparations made from cultures grown on agar at 37 C. 

 the organism is found to be a rod a little smaller than the 

 anthrax bacterium, occurring singly and in pairs and in occa- 

 sional filaments. 



Staining. In young cultures the bacilli are Gram posi- 

 tive but the granules are not differentiated by the Grain stain. 

 The spores stain readily by any of the ordinary methods. The 

 organism is motile and it is found on staining by van Ermen- 

 gem's method to be possessed of 10 or 15 flagella disposed 

 peritrichally, the flagella measuring in length about five times 

 the length of the bacillus itself. 



Cultivation. Jordan and Harris were able to cultivate 

 this organism on ordinary culture media. 



Agar. At 37 C. at the end of 24 hours, the surface is 

 more or less irregularly covered with a delicate veil-like 

 growth, which is more profuse at the end of from 48 to 72 

 hours and eventually may take on a semiviscid character in 

 some cultures. The color of the growth was grayish and sur- 

 face moist, smooth and glossy. There was no pigmentation 

 of the growth itself or of the medium. Gas was not produced. 

 The condensation-water growth was heavy, grayish-white in 

 color. No odor. 



Gelatin. If the organism is grown in a petri dish of 

 gelatin at 30 C. it is found at the end of 24 hours that the 

 whole of the medium is quite cloudy, with not infrequently 

 several small islets of pellicular material scattered over the 

 surface. The surface growth increases during the next four 

 days but never forms a complete film over the surface. On 



