BACILLUS ANTHRACIS. 425 



there any difference in the time required for their de- 

 velopment on the plates? 



From a potato culture of anthrax bacilli which has 

 been in the incubator for three or four days scrape 

 away the growth and carefully break it up in 10 c.c. 

 of sterilized physiological salt-solution. The more 

 carefully it is broken up the more accurate will be the 

 experiment. Place this in a bath of boiling water 

 and at the end of one, three, five, seven, and ten min- 

 utes make a plate upon agar-agar with one loopful of 

 the contents of this tube. Are the results on the plates 

 alike ? 



Determine the exact time necessary to sterilize ob- 

 jects, such as silk or cotton threads, on which anthrax 

 spores have been dried, by the steam method and by 

 the hot-air method. 



Prepare from the blood of an animal just dead of 

 anthrax a bouillon culture. After this has been in the 

 incubator for from three to four hours subject it to a 

 temperature of 55 C. for ten minutes. At the end 

 of this time make plates from it and also inoculate a 

 rabbit subcutaneously with it. What are the results ? 

 Are the colonies on the plates in every way charac- 

 teristic ? 



Inoculate six Erlenmeyer flasks of sterile bouillon, 

 each containing about 35 c.c. of the medium, from 

 either the blood of an animal just dead of anthrax or 

 from a fresh virulent culture in which no spores are 

 formed. 



