CHAPTEE XVI. 



Suppuration— staphylococcus pyogenes aureus— Staphylococcus pyogenes 

 albus and citreus— Staphylococcus epidermidis albus— Streptococcus 

 pyogenes— Micrococcus gonorrhoeBe — Biplococcus intracellularis men- 

 ingitidis— Bacillus pyocyaneus— Bacillus of bubonic plague. 



STAPHYLOCOCCUS PYOGENES AUREUS. 



Prepare a set of plates of agar-agar from the pus 

 of an acute abscess or boil that has been opened under 

 antiseptic precautions. Care must be taken that none 

 of the antiseptic used gains access to the culture-tubes, 

 otherwise its antiseptic eifect may be operative and the 

 development of the organisms interfered with. It is 

 best, therefore, to take a drop of the pus upon a plati- 

 num-wire loop after it has been flowing for a few sec- 

 onds ; even then it must be taken from the mouth of 

 the incision and before it has run over the surface of the 

 skin. At the same time prepare two or three cover- 

 slips from the pus. 



Microscopic examination of these slips will reveal the 

 presence of a large number of pus-cells, both multi- 

 nucleated and with horseshoe-shaped nuclei, some 

 threads of disintegrated and necrotic connective tissue, 

 and, lying here and there throughout the preparation, 

 small round bodies which will sometimes appear singly, 

 sometimes in pairs, and frequently will be seen grouped 

 together somewhat like clusters of grapes. (See Fig. 

 55.) They stain readily and are commonly located in 

 the material between the pus-cells ; very rarely they 

 may be seen in the protoplasmic body of the cell. 

 (Compare the preparation with a similar one made 

 870 



