TUBERCULOSIS. 115 



logical characters. How does it grow in bouillon, in gelatin, on agar, on 

 blood-serum, on potato? 



What animals are susceptible? 



Describe the effects of subcutaneous or intrathoracic inoculations. 



How is it differentiated from the preceding germ? 



Where is the Diplococcus intracellularis meningitidis found? 



By whom was it discovered? 



Give its morphology, its staining properties, its principal biologic charac- 

 ters? 



How is lumbar puncture performed? 



What animals are susceptible? 



How and where should the inoculation be performed? 



Who discovered the Micrococcus melitensis f 



Where was it found ''. 



State its morphology, staining, its biologic characters. 



What animals are susceptible ? 



In what dilution does the blood of cases of Malta fever agglutinate cult- 

 ures of this micrococcus? 



CHAPTER X. 



TUBERCULOSIS. 

 Bacillus Tuberculosis. 



History. That tuberculosis, the scourge of the human 

 race, was caused by a microorganism, had long been sus- 

 pected there is no doubt, but it was not until Koch's dis- 

 covery of the bacillus tuberculosis in 1882 that this was at 

 all proved. (Plate II.) 



Morphology. The Bacillus tuberculosis is a strict parasite. 

 It is aerobic and grows at the temperature of the human 

 body. It is a slender rod from 1.5 to 3.5 mikrons in length, 

 and from 0.2 to 0.5 mikron in breadth, occurring singly or in 

 pairs united by their narrow extremities. 



It is found in all tuberculous growths and secretions, but 

 especially in the sputum of tuberculous patients, where its 

 presence is the best confirmatory evidence of the existence 

 of the disease. 



Biologic Characters. It grows with difficulty on any of 

 the artificial media. Koch succeeded in growing it on blood- 

 serum. It does not grow in gelatin. It thrives best on 8 

 per cent, glycerin-agar or, in the mixture of Roux and 



