162 THE MORE CHRONIC INFECTIOUS DISEASES 



foreign body and probably not to any peculiar toxin. 

 No immunity or peculiar blood changes follow an 

 attack. The treatment is surgical and medical, the 

 latter being confined to the use of potassium iodide. 



Morphology and General Characteristics. The organ- 

 ism of actinomycosis is in the form of interwoven 

 threads, radiating from a centre, having thickened 



FIG. 46 



Actinomyces fungus ("ray fungus"): left, as seen in tissues under low 

 magnifying power; right, a fungus mass examined fresh under higher_ mag- 

 nifying power. (Abbott.) 



or bulbous ends. These ends are important as they 

 assist in species determination and possibly have some- 

 thing to do with multiplication of the germ. The 

 threads are about 75iro o" to ^oiro G- mcn wide, their 

 length being very variable. The bulbs measure from 

 6"o lro"o to -g~oVo mcn m width and vary in length. They 

 grow with reasonable freedom in the laboratory, 



