106 SPECIAL BACTERIOLOGY 



granulation tissue degenerating more quickly ; suppuration also being 

 more pronounced, accompanied by the formation of fistulae which 

 undermine the skin, passing through the muscular tissue, and by this 

 means the fungus spreads from the jaws or neck to the pleura and 

 ungs, and through the diaphragm into the peritoneal cavity. 



ACTINOMYCES MUSCULORUM SUIS. 



This organism was discovered by Diincker in 1884, in the muscles 

 of swine. Although resembling the Actinomyces bovis, it is not 

 identical (Giinther). 



STREPTOTHRIX HOFFMANI. 



This is another organism very similar in its growth to the 

 Actinomyces bovis. It is found in the air. 



Microscopical Appearances. It occurs as a branched mycelium, 

 with swollen, club-like ends. 



Staining Reactions. It is stained by the Gram method. 



Biological Characters. It is aerobic, growing only at a tempera- 

 ture of over 22 C. 



On Agar Media it grows in light brown warty colonies, which very 

 soon coalesce. 



Bouillon remains clear ; a thick sediment is formed. 



Potatoes There is no growth. 



Pathogenesis. For guinea-pigs and rabbits, only by subcutaneous 



injections ; a local abscess being formed, and in the pus actinomycotic- 



like tufts with club-shaped ends are sometimes present, distinguished 



from the Actinomyces bovis by the clubs staining the same as the threads. 



STREPTOTHRIX ACTINOMYCES HOMINIS (ISRAEL). 



This organism was discovered by Israel and Wolff in two cases of 

 human actinomycosis, and in its macroscopical, microscopical, and 

 staining reactions resembles the Actinomyces bovis. 



The differentiation in cultures is, however, well marked, as it 

 only grows luxuriantly under anaerobic conditions, and under aerobic 

 slightly or not at all. The optimum temperature is 37, and the 

 development is very slow. 



On Agar-Agar irregular opaque colonies are formed, which in seven 

 days attain the size of a pin-head ; usually coalescing. To obtain pure 



