512 



BACILLI WHICH PRODUCE SEPTIC^MIA 



slender and on the average shorter than the bacillus of mouse septi- 

 ca3mia. 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 threads which are straight or more or less 

 curved and twisted. Small refractive bodies may sometimes be dis- 

 tinguished in the rods, and these have been supposed by some authors 

 to be spores, but this has not been demonstrated. 



This bacillus stains readily with the ordinary aniline staining 

 agents and also by Gram's method. 



Biological Characters. A. facultative anaerobic, non-liquefy- 

 ing bacillus. According to Schottelius, the rothlauf bacilli are some- 



FIG. 134. Bacillus of rouget, from a pure culture. X 1,000. From a photomicrograph. (Roux.) 



times motile, but Fliigge states that other observers have not seen 

 them in active motion. Frankel says they have the power of volun- 

 tary motion. Eisenberg says that the bacillus of mouse septica3mia 

 is motionless, and Frankel says they " seem to be incapable of volun- 

 tary motion. " Baumgarten remarks : " Whether the bacilli exhibit 

 voluntary movements has not been determined." Although this 

 bacillus is not strictly anaerobic, it grows better in the absence of 

 oxygen than in its presence. Development occurs in various culture 

 media at the room temperature, but is more rapid in the culture 

 oven. In gelatin stab cultures no development occurs upon the 

 surface, but the growth along the line of puncture is very character- 

 istic; this consists of a delicate cloud-like, radiating growth, which 

 extends, in the course of a few days, almost to the walls of the test 

 tube. The rothlauf bacillus does not extend so rapidly through the 



