376 BACTERIOLOGY. 



simulating tuberculosis (" pseudotuberculosis clado- 

 thrica"). The organism quickly loses its pathogenic 

 properties under artificial cultivation. 



ACTINOMYCES PSEUDOTUBERCULOSIS. In 1897 



Flexner detected this organism in a consolidated and 

 caseous lung. The condition suggested tuberculosis. 

 The lesion consisted mainly of an inflammatory exuda- 

 tion that had undergone cassation, but in addition there 

 were present isolated nodules that in size and general 

 appearance were difficult to distinguish from miliary 

 tubercles. Giant cells were not seen. The streptothrix 

 was abundant in the lung, appearing as masses of con- 

 voluted, branching threads. The contours of the rods 

 were not quite uniform, the staining was irregular, and 

 occasionally a thread was seen that, toward its extrem- 

 ity, appeared to be breaking up into short segments. 

 No coccus-like forms were seen. It is stained best by 

 the Weigert method, when deeply stained masses sepa- 

 rated from one another by more or less clear spaces are 

 to be detected. The organism was not obtained in 

 culture, and no effect was produced on guinea-pigs 

 by subcutaneous inoculation with bits of the diseased 

 lung. 



