DYSENTERY, NOG AND CHICKEN CHOLERA. 199 



oculations against bubonic plague by injections of dead cult- 

 ures. This immunity seems to last for several weeks. 



Recently, observations have demonstrated that Yersin 

 r-iMMim has absolutely no protective or curative properties. 

 Ilaffkine's protective inoculations are still held in favor, 

 however. 



QUESTIONS. 



By whom and when was the Bacillus pestis discovered? 



Describe this bacillus. Its mode of staining. Its principal biologic char- 

 acters. 



What temperature suits its growth best? What is the effect of high tem- 

 perature? 



How does it grow on gelatin ? On agar ? On bouillon ? 



What is its behavior with regard to fermentation and to indol pro- 

 duction ? 



How does it affect milk? 



How is it affected by disinfectants? 



What animals are susceptible to this disease? 



How are inoculations performed? 



Describe the symptoms and lesions caused by inoculation. 



What three forms of bubonic plague are recognized in man? Which is 

 tiie most frequent? Which the most fatal? 



How does infection take place? 



What are the symptoms of the disease, and what the lesions in man ? 



How is immunity conferred in this disease? 



Does the serum in cases of plague contain agglutinating power? 



How does Yersin manufacture his protective serum? What does he claim 

 for it ? 



How does Haffkine practise his protective inoculations? 



CHAPTER XXII. 

 DYSENTERY, HOG CHOLERA, AND CHICKEN CHOLERA 



DYSENTERY. 

 Bacillus Dysenteriae. 



History. This bacillus was first found in the intestinal con- 

 tents and in the visceral walls and mesenteric glands in cases 

 of acute epidemics of dysentery by Shiga, in Japan in 1898, 

 and this observation was confirmed afterward by Flexner in a 

 study of dysentery of the Philippine Islands. It seems to 

 belong to the typho-colon group. 



