SUPPURATION. 189

zone of furuncles. Bockhart suspended a small portion
of an agar-agar culture in salt-solution, and scratched it
gently into the deeper layers of the skin with his finger-
nail; a furuncle developed. Bumnv injected the coccus
suspended in salt-solution beneath his skin and that of
several other persons, and produced an abscess in every
case.

The Staphylococcus aureus is not only found in the
great majority of furuncles, carbuncles, abscesses, and
other inflammatory diseases of the surface of the body,
but also plays an important role in a number of deeply-
seated diseases of the internal organs. Becker and others
obtained it from the pus of osteomyelitis, demonstrating
that if, after fracturing or crushing a bone, the Staphylo-
coccus was injected into the circulation, osteomyelitis
would result. Numerous bacteriologists have demon-
strated its presence in ulcerative endocarditis. Rodet
has been able to produce osteomyelitis without previ-
ous injury to the bones; Rosenbach was able to produce
ulcerative endocarditis by injecting some of the staphy-
lococci into the circulation in animals whose cardiac
valves had been injured by a sound passed into the
carotid artery ; and Ribbert has shown that the injection
of cultures of the organism may cause the valvular lesion
without the preceding injury.

The Staphylococcus aureus is an easy organism to ob-
tain, and can be secured by plating out a drop of pus in
gelatin or in agar-agar. Such a preparation, however,
generally does not contain the Staphylococcus aureus
alone,, but shows colonies of the Staphylococcus albus as
well. In addition to these two principal forms, one
sometimes discovers an organism identical with the pre-
ceding, except that its growth on agar-agar and potato
is of a brilliant lemon-yellow color, and its pathogeny for
animals much less. This is the Staphylococcus citretts of
Passet. It is not quite so common, and not so patho-
genic as the others, and consequently much less im-
portant.