ACTINOMYCOSIS 103 



actinomyces in man and in the lower animals, but 

 it is supposed now that only one exists. 



In cattle actinomycosis is characterized by the 

 presence of hard sweUings in and about the head, 

 particularly in the tongue and lower jaw, which 

 gradually soften, destroying the bones as well as 

 the soft parts, while the swelling continues to en- 

 croach upon the surrounding tissues, usually causing 

 great disfigurement. Death is usually due to the 

 mechanical obstruction caused by the hard tumors, 

 and not to any toxic effect of the bacteria. 



In man the infection is more general, with less 

 formation of the hard tumors, and more suppura- 

 tion, death usually occurring in a few weeks. 



Method of Infection. — The actinomyces is found 

 upon grain, barley especially, which would probably 

 account for the infection of cattle; but the manner 

 of transmission from one animal to another or to 

 man has not yet been explained. The cases occur- 

 ring in man. have often been in persons who have had 

 no contact or remote relation to either animals or 

 men suffering with the disease, and neither have they 

 handled any grain which might harbor the organ- 

 isms. 



