438 PATHOGENIC BACTERIA.

Kitasato found that mice, rats, guinea-pigs, and rabbits
are all susceptible; pigeons are immune. Julian Haw-
thorne, in his paper in the Cosmopolitan, speaks of hav-
ing seen cats and dogs dying of the disease, but no men-
tion is made of these animals in the scientific papers I
have. read. When blood, lymphatic pulp, or pure cul-
tures are inoculated into them, the animals become ill in
from one to two days, according to their size. Their eyes
become watery, they begin to show disinclination to take
food or to make any bodily effort, the temperature rises
to 41.5° C., they remain quietly in a corner of the cage,
and die with convulsive symptoms in from two to five
days.

Devell1 has found that frogs are susceptible to the dis-
ease.

Wyssokowitz and Zabolotni}'2 found monkeys to be
highly susceptible to plague, especially when inoculated
subcutaneously. When so small an inoculation was
made as a puncture with a pin dipped in a culture of the
bacillus, the puncture being made in the palm of the
hand or sole of the foot, the monkeys always died in
from three to seven days. In these cases the local edema
observed by Yersin did not occur. They point out the
interest attaching to infection through so insignificant a
wound and without local lesions.

According to Yersin, an infiltration or watery edema
can be observed in a few hours about the point of inocula-
tion. The autopsy shows the infiltration to be made up
of a yellowish gelatinous exudation. The spleen and
liver are enlarged, the former often presenting an appear-
ance much like an eruption of miliary tubercles. Some-
times there is universal swelling of the lymphatic glands.
Bacilli are found in the blood and in all the internal
organs. Very often there are eruptions during life, and
upon the inner abdominal walls there are petechiae and
occasional hemorrhages. The intestine is hyperemic, the

1 CentraM.f. Bakt. u. Parantenk., Oct. 12, 1897.

2 Ann. de F Inst. Pasteur, Aug. 25, 1897, xi., 8, p. 665.