ACTINOMYCES BOVIS. 445 



Distribution. 



(a) Outside the body: They have not been found, but 

 must frequently occur upon the beards of grains and grasses, 

 because infection most often depends upon the penetration 

 of a fungus-carrying barley barb, which is often found in 

 the actinomycotic swelling (Bostrom). (Compare Berest- 

 new, p. 447.) 



(b) In healthy body : Never found. 



(c) In diseased human organism : It is the cause of acti- 

 nomycosis. Principal ports of entrance: (1) Mucous 

 membrane of mouth and throat; (2) respiratory tract; 

 (3) intestine; (4) skin. Almost always beards and other 

 parts of grain are the vehicle; more rarely, wood. From 

 the primary areas the fungus is carried to all parts of the 

 body by means of wandering cells and emboli. The dis- 

 ease in man produces soft granulation tissue, which is not 

 encapsulated, and has a tendency to break down and to 

 spread slowly but extensively to the surrounding tissue 

 (chronic phlegmon). The formation of fistulas favors the 

 extension. More rarely there are distinct tumors, as in 

 cows. In the actinomycotic pus the actinomyces bodies 

 are found. (See under Microscopic Findings. ) There is 

 scarcely a tissue or an organ of the body in which the 

 actinomyces has not been demonstrated. Generalization 

 of the actinomyces throughout the body is rare (see Mess- 

 ner, C. B. xix, 487). 



In 1892, 421 cases in man were known. Recently acti- 

 nomycosis has also been observed in America. 



(d) In animals : Especially in cows (rarely in swine, 

 dogs, and horses). Formerly it was considered quite rare 

 (1 in 10,000 to 1 in 3000), but it evidently is much more 

 common, and simply overlooked. Sometimes it is epi- 

 demic. The localization is similar to that in man. Most 

 often its seat is in the marrow of the upper and lower jaw; 

 the marrow is traversed by soft granulation tissue and 

 denser connective-tissue masses, the medullary cavity is 

 enlarged, and new bone grows out from the periosteum 

 (bony tumor). In other cases the soft parts of the face 

 may be primarily attacked and the bones first involved 

 from without. Also the pharynx and the wall of the 

 stomaeh may be primarily attacked. The maxillary 



