392 MICRO-ORGANISMS AND DISEASE [chap. 



after twenty-four hours numerous colonies were noticeable 

 in the depth, those in the sugar gelatine were spherical 

 translucent masses of liquefied gelatine, those in the sugar 

 Agar whitish small dots not liquefying the Agar; at the 

 same time gas bubbles were present in connection with the 

 colonies, particularly in the sugar Agar. After forty-eight 

 hours the growth had so advanced, and the liquefaction of 

 the gelatine had become so extensive, that the lower half in 

 the test tube was completely liquefied, very shghtly turbid 

 by the growth ; on the surface of the liquefied growth gas 

 bubbles may be present or they may be altogether absent, 

 in the depth whitish cloudy flakes {see Fig. 148). 



Examining under the microscope such a liquefied culture 

 after two or three days' growth it was found to be made up 

 of rod-shaped or cylindrical bacilli, generally singly or in 

 chains of two, three or more rods ; they were mostly appa- 

 rently stationary, but here and there feeble locomotion could 

 be noticed, consisting in a wobbling or rolling slightly progres- 

 sive movement ; but only few such motile bacilli could 

 be seen. In some of the bacilli there was present a bright 

 oval spore, occasionally in the middle, but oftener near one 

 end. In the floccular masses at the bottom of the culture 

 tube spore-bearing bacilli were numerous, and even occa- 

 sionally a free spore. After three or'latest after four days 

 the whole of the sugar gelatine in the tube had become 

 liquefied by the growth, on the top there were gas bubbles ; 

 in the depth a white powdery precipitate which on micro- 

 scopic examination shows numerous free spores. When 

 such a cuUure is opened it has a distinct smell of butyric 

 acid ; when the liquefied gelatine is disturbed by moving in 

 it a platinum or glass rod, numerous gas bubbles rise up ; 

 the liquid when sucked up in a capillary pipette emits a con- 

 siderable amount of gas bubbles. When the culture tubes 



