384 BACTERIOLOGY. 



Cultures from the different organs or from the oederna- 

 tous fluid about the point of inoculation result in growth 

 of the bacillu anthracis. 



The amphibia, dogs, and the majority of birds are not 

 susceptible to this disease. Rats are difficult to infect. 

 Rabbits, guinea-pigs, white mice, gray house- mice, sheep, 

 and cattle are susceptible. Infection may occur either 

 through the circulation, through the air-passages, through 

 the alimentary tract, or, as we have just seen, through 

 the subcutaneous tissues. 



EXPERIMENTS. 



Prepare three cultures of anthrax bacilli one upon 

 gelatin, one upon agar-agar, and one upon potato. 

 Allow the gelatin culture to remain at the ordinary tem- 

 perature of the room, place the agar-agar culture in the 

 incubator, and the potato culture at a temperature not 

 above 18 to 20 C. Prepare cover-slips from each 

 from day to day. What differences are observed? 



Prepare two potato cultures of the anthrax bacillus. 

 Place one in the incubator and retain the other at a tem- 

 perature of from 18 to 20 C. Examine them each 

 day. Do they develop in the same way ? 



From a fresh culture of anthrax bacilli, in which 

 spore-formation is not yet begun (what is the surest 

 source fro'm which to obtain non-sporebearing anthrax 

 bacilli), prepare a hanging-drop preparation ; also a 

 cover-slip preparation in the usual way and stain it 

 with a strong gentian-violet solution, and another 

 cover-slip preparation which is to be drawn through 



