258 
M. S. ARLOINGL 
animals having peripneumonic lesions were more sensitive 
than healthy animals. And, besides, I convinced myself that 
complete cultures, under a given virulent state, would give 
to the bovine an equivalent equal to that produced by the 
serosity of the diseased lung inoculated according to Dr. 
Willems’ method, and without exposing him to any danger¬ 
ous condition. 
Of these facts more later on. To-day I desire to show: 
ist, that the essential agent of the virus acts like other or¬ 
dinary microbes; 2d, that this agent is the pneumobacillus. 
II.—Admitting that peripneumonic virulency is functions 
of a living particle, it must increase with the number of par¬ 
ticles existing in the serosity of the diseased lung. If this 
particle is an ordinary microbe, and if its vehicle can act for 
it as a media of culture in placing the serosity simply in the 
conditions where the microbe may multiply, its activity will 
increase to a certain degree and in proportion to the dura¬ 
tion of the culture. 
Consequently, if by inoculating under the skin of a bovine 
equal quantities of pulmonary serosity, collected pure and 
first submitted to an incubation at +35°, local effects are ob¬ 
tained and increase in proportion to the length of the incu¬ 
bation, one will conclude that the peripneumonic virulency 
is function of an ordinary microbe. Experiment has furnished 
evidences confirming the foregoing. 
Pulmonary serosity increases in virulency and becomes 
slightly cloudy in the hot air. The cloudiness is due to the 
numeric increase of the germs, to their multiplication, as it 
is proven by the culture in spread gelatine when this opera¬ 
tion is possible. 
From these experiences cannot one infer that the patho¬ 
genic agents of peripneumonia are living particles,. able to 
multiply in their natural vehicle ; in other words, are mi¬ 
crobes such as a certain number of those that we know ? 
HI-—Cultures of serosities, taken out of an incubative 
store, made in spread gelatine, have simultaneously shown an 
increase in the virulency and in the number of the germs.' 
