TRICHOMYCETES 



255 



difficulty here seems to depend in part upon the oxygen require- 

 ments of the organism. The material for culture should be 

 obtained from uncontaminated tissue containing the fungus. 

 If this is impossible, the granule of actinomyces should be washed 

 in several changes of sterile salt solution, then crushed between 

 sterile glass slides or, better, ground up in a sterile mortar with 

 a small amount of sterile sand. A series of dilution cultures 

 should then be made in tall tubes of melted. glucose agar cooled to 

 45° C, the tubes chilled in cold water and incubated at 37° C. 



Fig. 105. — Actinomyces bovis. The ray-fungus from cow. (Diagrammatic.) 



Colonies of the fungus may be expected to develop some distance 

 below the surface of the agar. Wolf and Israel were able to re- 

 produce the disease in animals (rabbits and guinea-pigs) by the 

 inoculation of pure cultures. More recently Harbitz and Gron- 

 dahP isolated twenty-seven strains of actinomyces, but their 

 inoculation experiments were wholly negative. It would appear 

 that other factors are essential to the development of actinomy-, 

 cosis in addition to the inoculation of the specific parasite. Many 

 authors regard the presence of bits of straw or sharp grains in 

 wounds of the mucous membrane of the mouth or pharynx as 

 important elements in predisposing to infection with actinomyces. 



' Amer. Journ. Med. Sciences, 191 1, Vol. CXLII, pp. 386-395. 



