368 BACTERIOLOGY. 



with the organisms than to any pathogenic powers pos- 

 sessed by the organism itself. 



Another spirillum that has been likened to that of 

 Koch is the one obtained by Miller from a carious 

 tooth. It has so many characteristics in common with 

 the organism of Finkler and Prior that Miller was 

 inclined to consider them identical. In morphology 

 they are indistinguishable. (See Fig. 74.) It grows 



FIG. 74. 



Spirillum of Miller. From agar-agar culture twenty-four hours old. 



rapidly, and, like the spirillum of Finkler and Prior, 

 causes rapid liquefaction of gelatin with the coincident 

 production of a peculiar aromatic odor. 



The colonies on gelatin plates appear after twenty- 

 four hours as small, transparent pits of liquefaction in 

 the centre of which can be seen a minute white point, the 

 colony itself. Under a low lens the largest of these 

 points are uniformly granular and regularly round, and 

 as a rule are surrounded by a peripheral zone that is 

 a little darker than the central portion of the colony. 

 The circumference is delicately fringed by short, cilia- 

 like prolongations of growth which are not as a rule 

 straight, but are twisted in all directions and can only 



