482 BACTERIOLOGY. 



to consider them identical. In morphology they are 

 indistinguishable. (See Fig. 85.) It grows rapidly, 



Fig. 85. 



/■ 



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



and, like the spirillum of Finkler and Prior, causes 

 rapid liquefaction of gelatin, with the coincident pro- 

 duction 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 luiifonnly granular and regularly round, 

 and, as a rule, are surrounded by a peripheral zone a 

 little darker than the central portion of the colony. 

 The circumference is delicately fringed with short, cilia- 

 like prolongations of growth which are not, as a rule, 

 straight, but are twisted in all directions and can only 

 be detected upon very careful examination. (See a, 

 Fig. 86.) When located deep in the gelatin the colonies 

 are round, sharply circumscribed, of a pale yellowish or 

 greenish-yellow color, and marked by very delicate irreg- 

 ular lines or ridges. After forty-eight hours the plate 

 containing many colonies is entirely liquefied, while that 

 containing only a few shows the presence of round, 

 sharply-cut, shallow pits of liquefaction that measure 

 from 2 to 10 mm. in diameter. They are a little denser 



