190 



BACTERIOLOGY 



develop, which adhere firmly to the mass, and on potato 

 there grows a dirty whitish-grey layer containing many 

 involution forms. 



Funnel-shaped area of 

 liquefaction 



Needle-track 



FIG. 72. THRUST-CULTURE IN GELATINE OF THE BACILLUS MEGATERIUM. 



Besides the above, the Bacillus prodigiosus, Bacillus sub- 

 tilis, Bacillus amylobacter, and Bacillus butyricus are met 



