MOUSE-SEPTICEMIA. 545 



perhaps identical, organism in the erysipelatous disease 

 which attacks the swine of many parts of Europe. 



There seem to be certain slight morphological and 

 developmental differences between these two organisms, 

 but Baumgarten, Gunther, Sternberg, and others have 

 regarded them as insufficient for the formation of sepa- 

 rate species, and have boldly described the organisms as 

 identical, while Lorenz has shown that immunity pro- 

 duced in the rabbit by one bacillus protects against the 

 other. The described differences are, indeed, so very 

 small that I think it well to follow in the path of the ob- 

 servers mentioned, pointing out in the description such 

 points of difference as may arise. 



The bacilli are extremely minute, measuring about 

 i.o x 0.2 fi (Sternberg). Fliigge, Frankel, and Eisenberg 

 find the Bacillus erysipelas suis somewhat shorter and 

 stouter than that of mouse-septicemia : there seems to 

 be a division of opinion upon this point. 



Sporulation has been described by some observers, but 

 nothing definite seems to be known upon this point. 



Motility is ascribed by some (Schottelius and Frankel) 

 to the Bacillus erysipelas suis, and is denied to the bacillus 

 of mouse-septicemia by others. The truth seems to be 

 that the motility of both organisms is a matter of doubt. 



No flagella have been demonstrated upon the bacillus. 

 It grows quite well both at the room-temperature and at 

 the temperature of incubation. It can grow well with or 

 without oxygen, but perhaps flourishes 

 a little better without than with it. It 

 is killed by a temperature of 52 ° C. in 

 fifteen minutes. 



The colonies upon gelatin plates can 

 first be seen on the second or third day, Fig. 123.— Colony 

 then appearing as transparent grayish of the baclllus of 



1 .,•■ 1 ■, j r mouse-septicemia: X 



specks with irregular borders, from go K 

 which many branched processes extend 

 (Fig. 123). Frankel describes them as resembling in 

 shape the familiar branched cells occupying the lacunae 

 35 



