PATHOGENIC BACTERIA. 369 



As a result of his research, Wright* comes to different conclusions from many 

 of those who have studied the ray-fungus. He regards the organism as essen- 

 tially anaerobic; seldom found in external nature; probably present in the normal 

 alimentary canal. He succeeded in obtaining club shapes in serum cultures, 

 and in producing nodules by inoculation of animals. The bodies called spores 

 by other observers are not to be regarded as spores. 



According to Wright's description, the organism represented by Fig. 89 would 

 have to be regarded not as the true ray-fungus but as one of its saprophytic 

 congeners. 



Besides the common actinomyces, there are numerous other ray-fungi, more 

 or less closely related, and whose pathogenic properties are not fully deter- 

 mined. Generally speaking, they appear to be essentially saprophytes, which 



FIG. 94. Actinomyces bovis, smear preparation from a pure culture, 

 stained by Gram's method. (X 1000.) 



occasionally become parasitic and pathogenic under especially favorable con- 

 ditions. A number of species have been found in air, dust, etc., some of them 

 chromogenic. Wolff and Israel described an anaerobic species, pathogenic 

 to man and animals. Madura disease, Madura foot, or mycetoma is a disease 

 occurring in India (rarely elsewhere), affecting one of the extremities, character 

 ized by swellings, nodular deposits and abscesses. Some cases are certainly 

 due to a member of the aetinomyces group. f 



Other branching organisms, some of them acid-poof, have been described 



* Wright. Journal of Medical Research. XIII., p. 349. 



fCompare Wright. Journal Experimental Medicine. Vol. III., p. 421. 



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