XI] BACILLI : SPECIFICALLY PATHOGENIC 247 



Petruschki described (Centralblatt f. Bakt. und Parasit. 

 No. 6/7, i8g6) a bacillus, occurring occasionally in the 

 typhoid stools and also other putrid materials, which coin- 

 cides in most points with the typhoid bacillus. This is the 

 bacillus facalis alkaligenes. It differs from the typhoid 

 bacillus in forming alkali in litmus-whey, the latter being an 

 acid former. 



