SECTION II 
SPECIAL BACTERIOLOGY 
CHAPTER VII 
THE STAPHYLOCOCCUS GROUP 
I. Historical 
The staphylococcus group were first carefully studied 
in 1879 by Koch, Ogston, Pasteur and Rosenbach. They 
are so called because of their appearance in irregular 
clusters (from Greek, meaning bunch of grapes). 
II. Morphology and Staining 
It is a coccus, round or spherical, diameter about 0.9 jx. 
They are usually arranged in clusters, but very young 
cultures may show diplococci (pairs). 
Staphylococci stain with all simple stains, and are 
Gram positive; they are nonmotile, have no spores, no 
capsules, no flagella. 
III. Cultural Characteristics 
Staphylococci grow readily on all plain media; they are 
aerobes and facultative anaerobes (that is, they may 
grow without oxygen). They form in 24 hours discrete, 
golden yellow colonies of various sizes. Gelatin is lique¬ 
fied. Milk is coagulated and acids (lactic and butyric) 
are formed. 
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