286 



A C TINOM YCOSIS. 



rubin, etc. ; sometimes a darkly -stained filament can be 

 seen running for a distance in the centre, and may have a 

 knob -like extremity. In many of the colonies in the 

 human subject the clubs are absent. In the ox, on the 

 other hand, where there are much older colonies, the clubs 

 constitute the most prominent feature, whilst in most 



FIG. 75. Actinomyces in human kidney, showing clubs radially 

 arranged and surrounded by pus. The filaments had practically dis- 

 appeared. 



Paraffin section ; stained with haematoxylin and rubin. x 500. 



colonies the filaments are more or less degenerated, and it 

 may sometimes be impossible to find any. They often 

 form a dense fringe around the colony, and when stained 

 by Gram's method retain the violet stain. They have, in 

 fact, undergone some further chemical change which pro- 

 duces the altered staining reaction. Clubs showing inter- 



