Cultivation 581 



colony. To the naked eye the deep colonies appear as small white points. They 

 rapidly reach the surface, begin liquefaction of the gelatin, and by the second day 

 appear about the size of lentils, and are situated in little depressions. Under the 





Fig. 240. Spirillum of Finkler and Prior, from an agar-agar culture. 

 (Itzerott and Niemann). 



X 1000 



microscope they are yellowish brown, finely granular, and are surrounded by 

 a zone of sharply circumscribed liquefied gelatin. Careful examination with a 

 high-power lens shows rapid movement of the granules in the colony. 



Fig. 241. Spirillum of Finkler and Prior; colony twenty-four hours old, upon a 

 gelatin plate. X 100 (Frankel and Pfeiffer). 



Gelatin Punctures. In gelatin punctures the growth takes place rapidly along 

 the whole length of the puncture, forming a stocking-shaped liquefaction filled 

 with cloudy fluid which does not precipitate rapidly; a rather smeary, whitish 



