590 



BACTERIOLOGY. 



under the microscope are seen to be finely granular and 

 yellowish or yellowish-brown in color; the colonies are 

 round with more sharply denned border, less coarsely 

 granular and darker in color than those of the comma 

 bacillus. Liquefaction of the gelatin around these col- 

 onies progresses rapidly, and at the end of forty-eight 

 hours is usually complete in plates where they are numer- 

 The surface colonies sink quickly into the gelatin 



ous. 



FIG. 80. 



Spirillum of Finkler and Prior. X 1100 diameters. 



and present a darker peripheral zone. The differenti- 

 ation between the Finkler and Prior and cholera spirilla 

 can readily be made in the earlier stages of their growth. 

 Later on, and especially when the cholera colonies are 

 the older, the diagnosis is not so easy. In gelatin stick 

 cultures liquefaction progresses much more rapidly than 

 in similar cultures of the cholera spirillum, and a stock- 

 ing-shaped pouch of liquefied gelatin is already seen 

 after forty-eight hours, which is filled with a cloudy 

 liquid. There is no bubble formation. The liquefac- 



