MOUSE-SEPTICEMIA. 33* 



In gelatin puncture-cultures the growth is quite cha- 

 racteristic, and the tendency of the bacillus to grow 

 anerobically is well shown (Fig. 108). The develop- 



FIG. 108. Bacillus of mouse-septicemia: gelatin puncture-culture three and a 

 half days old (Gunther). 



ment takes place all along the line of puncture, but is 

 more marked below than at the surface. The growth 

 takes place in a peculiar form, resembling superimposed 

 disks, each disk separate from its neighbors and consist- 

 ing of an area of clouded grayish gelatin reaching almost 

 to the walls of the tube. This growth develops slowly, 

 and causes a softening rather than an actual liquefaction 

 of the gelatin. 



Upon agar-agar and blood-serum a very delicate, trans- 

 parent grayish line develops along the path of the needle. 



The bacillus grows at the room-temperature, but much 

 better at the temperature of the incubator. 



The disease affects quite a variety of animals, notably 

 hogs, rabbits, mice, pigeons, and sparrows. The guinea- 

 pig, which is generally the victim of laboratory experi- 

 ments, is not susceptible to it. 



When mice are inoculated with a pure culture of this 

 bacillus, they soon become ill, lose their appetite, mope 

 in a corner, and are not readily disturbed. As the dis- 



