242 BACTERIOLOGY. 



twelve days repeat the inoculation, using the same cul- 

 ture ; if it again survives, inoculate it with the culture 

 preceding the one just used in the order of removal from 

 the incubator ; if it still survives, inoculate it with vir- 

 ulent anthrax. What is the result ? How is the result 

 to be explained? Do the cultures which were made 

 from these flasks at the time of their removal from the 

 incubators act in the same way toward animals as the 

 organisms growing in the flasks ? Is the action of each 

 of these cultures the same for mice, guinea-pigs, and 

 rabbits ? 



Prepare a 2 per cent, solution of sulphuric acid in 

 distilled water ; suspend in this a number of anthrax 

 spores ; at the end of three, six, and nine days at 35 C. 

 inoculate both a guinea-pig and^a rabbit. Prepare cul- 

 tures from this suspension on the third, sixth, and ninth 

 days ; when the cultures have developed inoculate a rab- 

 bit and a guinea-pig from the culture made on the ninth 

 day. Should the animal survive, inoculate it again after 

 three or four days with a culture made on the sixth day. 

 Do the results appear in any way peculiar ? 



