IN SUSCEPTIBLE ANIMALS. 511 
vein of a rabbit cause its death in from twenty-four to thirty-six hours; 
pathogenic also for house miceand for field mice. Atthe autopsy no notable 
pathological changes are observed. The bacilli are found in blood from the 
heart and in the capillaries of the various organs, but are not so numerous 
as in rabbit septiceemia; they show a special inclination to adhere to the 
margins of the red blood corpuscles. 
BACILLUS ERYSIPELATOS SUIS. 
Synonyms.—Bacillus of hog erysipelas; Bacillus des Schweine- 
rothlauf (Léffler, Schiitz) ; Bacille du rouget du pore (Pasteur) ; Ba- 
cillus of mouse septicemia; Bacillus murisepticus (Fliigge) ; Bacil- 
lus des Mauseseptikamie (Koch). 
The bacillus of mouse septiceemia, first described by Koch (1878), 
resembles so closely in its morphology, characters of growth, and 
pathogenic power the bacillus of Schweinerothlauf of Léffler and 
Schiitz (1885) that they can scarcely be considered as distinct spe- 
cies, although, from slight differences which have been observed, they 
are perhaps entitled to separate consideration as varieties of the 
same species. Fliigge, Eisenberg, Frankel, and other authors, while 
recognizing the fact that the bacilli from the two sources closely re- 
semble each other, apparently do not consider 
them identical, and describe them separately. 
Baumgarten, on the other hand, describes them 
under one heading and considers it highly prob- 
able that they are identical, although he also 
admits slight differences in the morphological 
characters and growth in culture media. These 
differences are, however, no greater than we 
have in artificially produced varieties of other 5, 195 Bacitius of 
well-known microorganisms, and we think it mouse septicemia in leu- 
best to follow Baumgarten in describing them ‘Svs ra rer 
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 
upon contracted a fatal form of septicemia, and the bacillus under 
consideration was found in their blood. The bacillus of Schweine- 
rothlauf was obtained by Léffler and by Schitz from the blood and 
various organs of swine which had succumbed to the infectious 
malady known in Germany 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 Ei- 
senberg, but Baumgarten states that they are somewhat more 
