NOT DESCRIBED IN PREVIOUS SECTIONS. 551 
prominent symptoms in the cases of cholera infantum in which the 
proteus bacteria were found were drowsiness, stupor, emaciation 
and great reduction in flesh, more or less collapse, frequent vomiting 
and purging, with watery and generally offensive stools.” 
The researches of Krogius, Schnitzler, Schmidt and Aschoff, and 
others, show that in cases of cystitis and of pyelonephritis this bacil- 
lus is frequently found in pure cultures, or associated with other bac- 
teria. The authors last named state that in sixty cases of cystitis 
reported by various authors the colon bacillus was found in pure cul- 
tures, and in thirteen cases the proteus of Hauser. Next to Bacillus 
coli communis Proteus vulgaris appears to be the microérganism 
most frequently concerned in the etiology of pyelonephritis. 
Levy (1895) isolated from sour yeast a bacillus, which he identified 
as “Proteus Hauseri,” and made numerous experiments on dogs to 
test its pathogenic power. From five to ten cubic centimetres of a 
liquefied gelatin culture injected into the circulation, through a vein, 
caused the typical symptoms of “sepsin poisoning,” as formerly de- 
scribed by Bergmann and Schmeideberg (1868). In two dogs which 
died at the end of forty-eight hours the intestinal tract was found in 
a condition of intense hemorrhagic infiltration. The spleen and 
glands of the mesentery were much enlarged. But a bacteriological 
examination gave an entirely negative result, showing that death 
resulted from toxeemia and not from septicemia. Further experi- 
ments showed that the dried precipitate obtained from liquefied gela- 
tin cultures, by the addition of alcohol, had the same pathogenic 
action on dogs, rabbits, and mice as cultures containing the living 
-bacilli. That a similar pathogenic effect is produced in man by the 
products of growth of this bacillus was shown by the following facts: 
While conducting his experiments Levy had an opportunity to make 
a bacteriological examination in the case of a man who died after a 
brief attack of cholera morbus. From the vomited material and the 
stools he obtained a pure culture of proteus; but the blood, collected 
at the autopsy, was sterile. In the mean time seventeen other per- 
sons who had eaten at the same restaurant were taken sick in the same 
way. Upon an examination at the restaurant it was found that the 
bottom of the ice chest in which the proprietor kept his meats was 
covered with a slimy, brown layer, which gave off a disagreeable 
odor. Cultures from this gave the proteus as the principal micro- 
organism present. Levy concludes from his own investigations and 
those of other bacteriologists that in so-called “flesh-poisoning” bac- 
teria of this group are chiefly at fault, and that the pathogenic effects 
are due to toxic products evolved during their development. 
