474 BACTERIOLOGY. 



It is supplied with a single flagellum at one of its 

 ends, and is therefore motile. 



Fig. 79. 



Vibrio protms (Finkler-Prior bacillus), from culture on agar-agar twenty- 

 four hours old. 



It, like the comma bacillus, readily undergoes degen- 

 erative changes under conditions unfavorable to growth, 

 and presents the variety of shapes grouped under the 

 head " involution-forms." According to Buchner, this 

 is especially the case when the medium in which they 

 are growing contains glucose (5 per cent.) or glycerin 

 (2 per cent.). 



CuLTUEAL Peculiarities. — On gelatin plates the 

 development of its colonies is far more rapid, and lique- 

 faction far more extensive, than in the case of the 

 cholera spirillum. After twenty-two to twenty-four 

 hours in this- medium at 20° to 22° C. the average size of 

 the colonies is about double that of the comma bacillus. 

 The colonies are darker and denser, and do not pre- 

 sent under a low-power lens the same degree of granula- 

 tion and subsequent lobulation, and they do not become 

 serrated or scalloped around the margin, as is the case 

 with Koch's organism. After twenty-two to t^venty- 

 four hours they are usually nearly round, regularly 

 granular, and more or less sharply defined. (See Fig. 

 80, a.) At times they may show indefinite markings 

 or creases, somewhat suggestive of lobulations. After 



