250 BACTERIOLOGY. 



When magnified they appear in the earliest stages as 

 minute aggregations of small cells, the nuclei of which 

 stain intensely. Almost always there can be seen about 

 the centre of these cell-accumulations evidences of pro- 

 gressing necrosis. The normal structure of the cells of 

 the tissues will be more or less destroyed ; there will be 

 seen a granular condition due to cell-fragmentation; at 

 different points about the centre of this area the tissue 

 will appear cloudy and the tissue-cells will not stain 

 readily. All about and through this spot will be seen 

 the nuclei of pus-cells, many of which are undergoing 

 disintegration. In the smallest of these beginning ab- 

 scesses the staphylococci are to be seen scattered about 

 the centre of the necrotic tissue, but in a more advanced 

 stage they are commonly seen massed together in very 

 large numbers in the form commonly referred to as 

 emboli of microcoGoi. 



The localized necrosis of the tissues which is seen at 

 the centre of the abscess is the direct result of the 

 action of a poison produced by the bacteria, and repre- 

 sents the starting-point for all abscess-formations. 



When the process is farther developed the different 

 parts of the abscess are more easily delected. They 

 then present in sections somewhat the following condi- 

 tions: at the centre can be seen a dense, granular mass 

 which stains readily with the basic aniline dyes and, 

 when highly magnified, is found to be made up of 

 staphylococci. Sometimes the shape of this mass of 

 staphylococci corresponds to that of the capillary in 

 which the organisms became lodged and developed. 

 Immediately about the embolus of cocci the tissues are 

 seen to be in an advanced stage of necrosis. Their 

 structure is almost completely destroyed, though it is 



