144 ESSENTIALS OF BACTERIOLOGY 



colon group described by Widal, Gwyn, Schottmiiller, and 

 others. They are of importance, since they produce fevers 

 clinically resembling a mild form of typhoid, but which are 

 rarely fatal. They may be the sole cause of the disease, and 

 also occur together with the typhoid bacillus in mixed and 

 secondary infections. Morphologically, they resemble the 

 typhoid bacillus, but differ from it culturally and give their 

 own serum reactions with the blood of affected patients. 

 They ferment glucose, but not lactose or saccharose; litmus 

 milk at first becomes acid, but later grows alkaline and is not 



Fig. 62. Bacillus botulinus, with spores. Pure culture on sugar- 

 gelatin. Van Ermengem prep. (Kolle and Wassermann). 



coagulated. On potato a slight visible growth occurs; in- 

 dol is usually not formed. Typhoid sera do not agglutinate 

 paracolon bacilli, and vice versa; also different paracolon 

 infections may not agglutinate each other. 



Bacillus Botulinus (Van Ermengem) . An anaerobic ba- 

 cillus cultivated by Van Ermengem in 1896 from ham w r hich 

 had caused poisoning. 



Form. A large bacillus with rounded or spindle-shaped 

 ends, and often with oval terminal spores, motile, with lateral 

 flagella (Fig. 62). 



