C. THE SEPTIC DISEASES.

CHAPTER I.
ANTHRAX.

disease of cattle known as anthrax or ct splenic
fever " is of infrequent occurrence in this country and in
England. In France, Germany, Hungary, Russia, Persia,
and the East Indian countries it is a dreaded and common
malady which robs herdsmen of many of their valuable
stock. Siberia perhaps suffers most, the disease being so
exceedingly common and malignant as to deserve the
name 'c Siberian pest.'' Certain local areas, such as the
Tyrol and Auvergne, in which it seems to be constantly
present, serve as distributing foci from which the disease
spreads rapidly in summer, afflicting many animals, and
ceasing its depredations only with the advent of winter.
It seems to be distinctly a disease of the summer season.

The animals most frequently affected are cows and
sheep. Among our laboratory animals white mice,
guinea-pigs, and rabbits are highly susceptible; dogs,
cats, most birds, and amphibians are almost perfectly
immune. White rats are infected with difficulty. Man
is only slightly susceptible, the manifestation of the dis-
ease as seen in the human species being different from
the same disease in the lower animals in that it is usually
a local affection—malignant carbuncle—and only at times
gives rise to a general infection.

Anthrax was one of the first of the specific diseases
proven to be caused by a definite micro-organism. As
early as 1849, Pollender discovered small rod-shaped
bodies in the blood of animals suffering from anthrax,
but the exact relation which they bore to the disease was
not pointed out until 1863, when Davaine, by a series of
interesting experiments, proved to most unbiased minds
their etiological significance. The further confirmation

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