A STUDY OF THE MICROBES OF PUS. 
723 
The paper was illustrated by cultures of the germ in agar- 
agar, as well as finely executed water-colored sketches. 
Summary of Experiments. —One*of the unfavorable cir¬ 
cumstances connected with this work is the immunity pos¬ 
sessed by some mice and rats. While some would give affir¬ 
mative results with a certain organism, others would not 
become affected by several inoculations. Of the house mouse 
and rat, the mouse seemed to possess the least immunity. 
Again, the results varied according to the manner of making 
the inoculation ; while the organisms are placed well undei 
the skin, septic poisoning is more liable to follow, and in some 
instances when large numbers are introduced the shock to 
the system will be so great that death results before any le¬ 
sions are formed. Those inoculations made externally upon 
an abraded surface are more liable to produce suppuration at 
seat of inoculation, followed in some instances by death in 
three or four days. 
One fact conclusively proven is that the suppuration fol¬ 
lowing the inoculations is a direct result of the roll of the 
micro-organism therein introduced. As in each instance after 
inoculating with a certain germ, the same germ was obtained 
from the lesion produced by the inoculation. In some in¬ 
stances pure cultures of the inoculating organism weie ob¬ 
tained from the spleen and liver after death, death in these 
cases being due to septic poisoning. From this fact it will be 
seen that as suppuration is an evidence of a diseased condi¬ 
tion due to the roll of the micro organism, medical agents 
which would injure their vitality or destroy them would be 
indicated. 
Of the germs isolated, the pyocyaneus seems to be the 
most malignant, producing death in from ten to twelve hours 
in mice and rats. This organism was found only in wounds 
infected from the atmosphere. The aureus, according to the 
accounts of others and also proven by my work, is the most 
often found when the infection comes from within (the blood 
or tissues). Of the non-pathogenic organisms isolated in the 
course of my experiments two specimens were obtained from 
closed abscesses, each being apparently pure; suggesting 
