284 MANUEL OF BACTERIOLOGY. 



bacteria, which can be demonstrated by cultivation, and, as a 

 rule, also in smears made and stained upon cover-glasses. 

 The bacteria in ordinary suppuration lie, for the most part, out- 

 side the pus-cells, though some of them maybe found in the pus- 

 cells. In the case of the gonococcus and the Diplococcus in- 

 tracellularis meningitidis they are characteristically found in 

 pairs, inside of, or at least attached to, the pus-cells. The 

 character of the suppuration differs somewhat with the different 

 species of pyogenic bacteria. The kind of abscess above de- 

 scribedlocalized and having a central slought, usually rather 

 slow in progress is typical for the Staphylococcus pyogenes 

 aureus, which is prone to produce circumscribed areas of sup- 

 puration. The Sterptococcus pyogenes, on the other hand, 

 of tener leads to suppuration of a more diffused character, such as 

 we see in cellulitis and erysipelas; but either organism may, at 

 times, produce the effects usually characteristic of the other. 

 Pus having a blue or green tinge generally owes the color to 

 the presence of the Bacillus pyocyaneus. The commonest 

 pus producing organism is then the Staphylococcus pyogenes 

 aureus, and next to that the Streptococcus pyogenes. Among 

 the other pyogenic bacteria the following may be named: 



Staphylococcus pyogenes albus, including Staphylococcus 

 epidermidis albus; streptococcus of erysipelas (probably iden- 

 tical with Streptococcus pyogenes); gonococcus; Diplococcus 

 mtracellularis meningitidis; Staphylococcus pyogenes citreus; 

 Micrococcus tetragenus; Micrococcus pyogenes tenuis, which 

 may be the same as the Micrococcus lanceolatus; Staphy- 

 lococcus cereus albus and flavus. 



Pus-formation may also be due to Micrococcus lanceolatus, 

 Bacillus pyocyaneus, Bacillus proteus, Bacillus coli communis, 

 Bacillus pyogenes fcetidus, Bacillus pneumonia (of Friedlander), 

 Bacillus aerogenes capsulatus, the ray fungus of actinomycosis, 

 and possibly the bacillus of bubonic plague. Besides these 

 organisms, there are others whose effects are usually more 



