VARIETIES OF ACTINOMYCES 



295 



to the colour of the growths, 

 and a similar condition may 

 obtain in the case of the 

 human subject. Further- 

 more a considerable number 

 of streptothrices have been 

 found in cases of disease in 

 the human subject, the as- 

 sociated lesions varying in 

 character from tubercle-like 

 nodules on the one hand to 

 suppurative processes on the 

 other. The organisms culti- 

 vated from such sources 

 differ according to their 

 microscopic characters (for 

 example, some form "clubs" 

 whilst others do not) ac- 

 cording to their conditions 

 of growth, staining reac- 

 tions, etc. Of these only a 

 few examples may here be 

 mentioned, but it may be 

 noted that the importance 

 of the streptothrices as 

 causes of disease is con- 

 stantly being extended. 

 Wolff and Israel cultivated 

 from two cases of "actino- 

 mycosis " in man a strep- 

 tothrix which differs in so 

 many important points from 

 the actinomyces of Bostrom 



FIG. 102. Section of a colony of actinomyces 

 from a culture in blood serum, showing the 

 formation of clubs at the periphery. x 1500. 



Fia. 101. 1 Shake cultures of actinomyces in 

 glucose agar, showing the maximum 

 growth at some distance from the sur- 

 face of the medium. 



that it is now regarded 

 as a distinct species. An- 

 other species was culti- 

 vated by Eppinger from a 

 brain abscess, and called 

 by him "cladothrixaster- 

 oides," from the appear- 

 ance of its colonies on 

 culture media. A case 

 of general streptothrix 

 infection in the human 

 subject described by 

 MacDonald was probably 

 due to the same organism 

 as Eppinger's. In the 

 tissues it grows in a 

 somewhat diffuse manner 

 and does not form clubs ; 



1 For Figs. 101 and 102 

 we are indebted to Dr. J. Homer Wright of Boston, U.S.A. 



