STKEPTOCOCCUS PYOGENES 201 



Staphylococcus cereus flavus is differentiated by the yellow 

 colour exhibited in its cultures. In addition to these, Von 

 Schr otter and F. Winkler discovered also the Staphylococcus 

 cereus aureus, distinguished from both the others by the 

 orange-red colour of the colonies, and by its slower growth. 

 These microbes are also constantly found in the nasal 

 secretion in cases of coryza. The Staphylococcus cereus may 

 also occur in the interior of pus corpuscles ; but the cells 

 may then be arranged in diplococci, and in the pus of 

 urethritis it may be confounded with the gonococcus. The 

 latter, however, is bleached by Gram's method, whereas the 

 Staphylococcus cereus retains its colour. 



Streptococcus pyogenes. In phlegmonous suppurative 

 processes the Streptococcus pyogenes described by Kosenbach 

 is constantly present, and is probably identical with the 

 Streptococcus erysipclatis of Fehleisen (p. 113). It is 

 found, however, not only in erysipelas but also in puerperal 

 processes occurring in lying-in women. It does not liquefy 

 gelatine, and forms fine punctiform colonies, while in 

 thrust-cultures a thin delicate film appears around the 

 puncture (fig. 77). On agar minute dots resembling dew- 

 drops occur along the streak, and range themselves into a 

 ribbon-like stripe. The elements so far alter upon potato 

 that some individual cells appear larger, and others smaller, 

 than usual. It grows better at incubation temperature 

 than at that of ordinary rooms, but growth is usually slow 

 at best. Transmission of cultures into the lymph-channels 

 sets up a typical erysipelas, according to E. Fraenkel. 



The Micrococcus of gonorrhoea. The infectious nature of 

 gonorrhoeal secretion is due, as shown by Neisser, to cocci 

 which have received the name of Gonococci, and which can 

 easily be recognised in the secretion owing to their arrange- 

 ment in pairs. The individual cells are reniform, and may be 

 found in the pus arranged round the nuclei in the interior 

 of the cells, but not in groups (fig. 78), and are distinguished 



