120 LEPROSY AND SYPHILIS. 



higher bacteria, being probably a streptothrix, closely related to 

 the actinomyces. 



QUESTIONS. 



When and by whom was the Bacillus tuberculosis discovered ? How does 

 the bacillus behave in the presence of oxygen ? 



What is the size of the tubercle bacillus? In what tissues and secretions 

 of tuberculous animals is it usually found ? How is it best artificially grown ? 

 What temperature is most favorable fur its growth? How high a temperature 

 does it resist? 



Give two methods of staining the tubercle bacillus in cultures or in the se- 

 cretions of animals. Give the mode of staining the bacteria in tissue? What 

 has given rise to the idea of spores in the bacillus? 



What animals besides man are the most susceptible to tuberculous diseases? 

 What two forms of infection follow inoculation of this bacillus? What is the 

 usual mode of infection in man ? 



Mention some cases of localized tuberculosis in man. How are animals in- 

 oculated to produce the disease ? What are the usual infecting agents in man ? 



What part does tuberculous milk or tuberculous meat play in the dissem- 

 ination of tuberculosis? 



What was the subject of Koch's paper at the Congress of Tuberculosis, 

 in 1901? 



What part does heredity play in the transmission of tuberculosis? 



What is tuberculin ? 



What diagnostic purpose does tuberculin serve ? 

 How is tuberculin prepared ? 



What is meant by Tuberculin A, O, and E ? 



Why has the tubercle bacillus been thought to be a streptothrix? 



CHAPTER XI. 



LEPROSY AND SYPHILIS. 



LEPROSY. 

 Bacillus Leprae. 



History. The specific cause of leprosy is a bacillus known 

 as the Bacillus leprce, discovered by Hansen, and confirmed by 

 Neisser, in 1879. 



The bacillus is found a. in the tissues of leprous patients, 

 and b. in the secretions, with the exception of the urine. It 

 has never been found in the blood. 



Morphology. The bacilli are small straight rods with 

 pointed ends, sometimes curved, measuring from 5 to 6 mi- 



