STREPTOTHRICOSIS. 471 



similar characters, the latter ranging from the branching bacteria through 

 the nonbranching filamentous Leptothrix and the pseudo-branching 

 Cladothrix, to the budding Oidia or Blastomyces. 



The only question of doubt regarding the expediency of our generic 

 classification is raised by the very thorough and exhaustive work of 

 James Homer Wright, who has brought forward some strong arguments 

 in favor of making two genera out of the group of organisms under 

 discussion. 



As may be remembered, Wright separates this group into two genera ; 

 Actinomyces and Nocardia. He defines Actinomyces accurately and 

 places all the organisms which he thinks do not come within this defini- 

 tion into the genus Nocardia. 



Actinomycosis is defined as : 



"A suppurative process combined with' granulation tissue formation, the pus of 

 which contains characteristic granules of 'drusen' ' composed of dense aggregates 

 of branched filamentous microorganisms and their transformation of degenera- 

 tion products. In the term transformation products are included the charac- 

 teristic, refrangent, club-shaped bodies radially disposed at the periphery of the 

 granule, for these bodies have long since been clearly shown to arise by a trans- 

 formation of the peripheral filaments. They may or may not be present at the 

 periphery of the granule." 



Wright, in his further discussion of the organisms, emphasizes the 

 following points as being characteristic of Actinomyces. 



Club formation in tissues, anaerobism, granule formation, peculiarities 

 in culture media, morphology and action when injected into laboratory 

 animals. However, some of these distinctions were not constant even 

 in the author's series of cases. 



If we accept Wright's definition of actinomycosis, some of the organ- 

 isms termed Nocardia by the author must be included as etiologic 

 factors in actinomycosis, because the requirements are fulfilled by 

 microorganisms not included in his description of the organism which 

 he considers the specific cause of the disease, and furthermore, if his 

 definition and description of Actinomyces be accepted as sufficient for 

 genus determination, other genera could be removed from the group 

 with almost, if not with equally good cause. However, some of the 

 principal characteristics given for Actinomyces are not peculiar to his 

 organisms. Most of these are differences in degree only from other 

 members of the group, and are not specific, and in some instances, as 

 we have demonstrated by work with original cultures, Wright's conclu- 

 sions, based upon a study of the literature, are wrong. His observations 

 regarding 8. caprce Silberschmidt, and 8. madurce Vincent are examples 

 of this. Wright states that Vincent's case was probably one of actino- 

 mycosis, and that Silberschmidt worked with mixed cultures. We have 

 had cultures from the original strains of both these organisms in our 

 hands and are able to state positively that the bacillus- and coccus-like 



