IN SUSCEPTIBLE ANIMALS. 443 



it best to follow Baumgarten in describing them under a single 

 heading. 



Koch first obtained this bacillus by injecting putrefying blood or 

 flesh infusion, during the first days of putrefactive change, beneath 

 the skin of mice. A certain proportion of the animals experimented 



FIG. 135. Bacillus of mouse septicaemia in leucocytes from blood of mouse, x 700. (Koch.) 



upon contracted a fatal form of septicaemia, and the bacillus under 

 consideration was found in their blood. The bacillus of Schweine- 

 rothlauf was obtained by Loffler and by Schiitz from the blood and 

 various organs of swine which had succumbed to the infectious 

 malady known in Garmany as rothlauf and in France as rouget. 



Morphology. Extremely minute bacilli, about 1 /* in length and 

 0.2 /^ in diameter. The Schweinerothlauf bacilli are described as 

 somewhat thicker and longer by Fliigge, by Frankel, and by Eisen- 

 berg, but Baumgarten states that they are somewhat more slender and 



Fro. 136. Bacillus of rouget, from a pure culture. X 1,000. From a photomicrograph. (Roux.) 



on the average shorter than the bacillus of mouse septicaemia. The 

 bacilli are solitary, or in pairs the elements of which are often united 

 at an angle; occasionally a chain of three or four elements may be 

 observed, and in old cultures the bacilli may grow out into short 



