272 EXAMINATION OF PUS. 



must be remembered that when plague buboes begin to soften, the 

 plague bacilli may be replaced by ordinary pus organisms. 



It is remarkable how frequently we get pure cultures from abscess 

 material. In purulent material from abdominal abscesses we are apt 

 to obtain mixed cultures, especially the colon bacillus and B. pyocy- 

 aneus, in addition to ordinary pus organisms. 



When it is a question between streptococci and pneumococci, it is 

 well to inoculate a mouse; the capsulated pneumococci at the autopsy 

 make the diagnosis. 



Animal inoculation is also necessary in plague and glanders, and 

 possibly anthrax. When tetanus is suspected, it should be examined for 

 as described under Tetanus. Tuberculosis should also be identified by 

 inoculating a guinea-pig, as well as by acid-fast staining and culture, if 

 there be any doubt as to the nature of the material. 



The black or yellow granules of madura foot, as well as those of 

 actinomycosis, should be examined as recommended in the section on 

 fungi. 



Amoebae, coccidia and larval echinococci may be found in purulent 

 material, as may also various other animal parasites, as fly larvae, 

 sarcopsyllae, etc. 



