150 BACTERIOLOGY 



regarding fthe presence of the typhoid bacillus, the experi- 

 ment of growing it on potato is indispensable. In three or 



Superficial coating upon the 

 gelatine, which is not liquefied 



Xeedle-track 



FIG. 56. THRUST-CULTURE IN GELATINE OP THE BACILLUS OF TYPHOID FEVER. 

 XIXTH DAY. (After Baumgarten ) 



four days at room temperature, and in as little as two at 

 that of the incubator, there appears on the surface a moist, 

 even gloss, although no deposit can be seen even in the part 



