352 MEDICAL BACTERIOLOGY 



b. Examination of discharge. 



1. Microscopical examination usually without result. 



2. Cultures, glycerine agar and potato from pus. 



c. Animal inoculations, Straus' method. 

 Bacillus pestis. 



a. Make plate cultures from blood and buboes and work up 

 colonies. 



b. Make subcutaneous inoculation into guinea pigs from bubo, 

 and if death ensues search for B. pestis. 



Pseudomonas aeruginosa (B. pyocyaneus). Easily recognized 

 by its culture characters. 



Bacterium Welchii (gas bacillus). 



This germ is non-pathogenic for rabbits, but Welch and Flexner 

 have shown that if a rabbit be inoculated intravenously with 0.5 to 

 1 cc. of a bouillon culture and killed after a lapse of 5 or 10 minutes. 

 and the animal kept at 18-20 C. for 24 hours or at30-35 C. for 

 4 to 6 hours, the organism will multiply in the blood and produce 

 large quantities of gas in the vessels and organs. This effect is 

 characteristic. 



Bacillus oedematis (B. malignant oedema). 



a. Make cover-glass preparations from fluid of affected parts. 



b. Also make anaerobic cultures. If material contains spores It 

 should be heated to 80 C. for 10 minutes before it is seeded. 



Bacillus tetani. 



a. Make cover-glass preparations from pus and search for drum- 

 stick bacillus. 



b. Make dextrose bouillon and agar-plate cultures and develop 

 in hydrogen. 



c. Inoculate animals with the discharge, and also with the bouil- 

 lon culture, and watch for characteristic symptoms. 



Streptothrix bovis (actinomyces). 



a. Place one of the minute sulphur-yellow nodules in a drop of 

 glycerine on a glass slide and then apply gentle pressure. 



b. Even the low powers of a compound microscope will then show 

 something of the clustered arrangement which can be more carefully 

 studied under a higher power. 



c. Intraperitoneal inoculation of guinea pig. One month later, 

 nodules on peritoneum. 



Ameba coli. 103. 



REFERENCES, v. J. 405 ; Si. 514 and 518. See also texts under 

 the various organisms. 



