MICROBIAL DISEASES OF MAN AND ANIMALS. 581 



generally spoken of as fungi. Antinomyces bovis is commonly known as 

 the ray-fungus (Fig. 98). Its relation to the disease of actinomycosis is 

 probably specific but it is frequently aided by pus producing bacteria. 



It is believed that the Actinomyces vegetate on various grasses, especi- 

 ally wild barley, and that infection occurs by inoculation with the awns 

 and barbs of such grasses through the mucous membrane of the mouth 

 or other portions of the alimentary tract. 



Infection by inoculation is the most common method of introducing 

 the disease; but infection by inhalation evidently occurs in some cases. 



FIG. 98. Actinomyces bovis. The ray-fungus from cow. (Diagrammatic.) (After 



Williams.) 



It seems probable that some special stage of development for the Acti- 

 nomyces is necessary either within the diseased animal body or upon some 

 plants, in order that it may be able to infect animal bodies, for direct 

 inoculation by pus has usually given negative results. Inoculation by 

 bits of diseased tissue occasionally gives positive results. 



It is evidently not a producer of active toxins for the disease dis- 

 turbances are apparently due to harmful growth in the tissues and to 

 secondary infection. 



Suppuration is one of the conspicuous features as is also the develop- 

 ment of much new granulation tissue which tends to degenerate at the 

 center. Soft organs affected by this parasite show a tendency to multiple 

 abscesses. 



