73 



Examine microscopically the bouillon and agar cultures 

 in both hanging drop and stained cover-glass preparations. 

 Stain a preparation with each of the three ordinary staining 

 solutions heretofore used. 



Measure a few of the bacteria in a stained preparation and 

 make a drawing of them magnified looo diameters. 



Make a series of 3 agar plates from the bouillon culture. 



Examine sections of animal tissue containing anthrax 

 bacteria. Make and examine a few cover-glass preparations 

 from the liver of an animal (guinea-pig or rabbit) which 

 has just died of anthrax. (This will be furnished by the 

 instructor). 



EXERCISE XLIII. 



BACTERIUM (BACILLUS) ANTHRACIS (continued). 



§125. General directions. Re-examine all of the cul- 

 tures of Bacterium anthracis and describe any changes in 

 their appearance which may have taken place. 



Examine the agar culture for spores in (i) a hanging- 

 drop preparation, and (2) a stained cover-glass preparation. 

 Describe the appearance of the bacteria and spores in a 

 preparation from each. 



Stain the spores (Exercise XVII.) 



Study and describe the appearance of the colonies on the 

 agar plates. Make an outline drawing of a few of the sur- 

 face and deep colonies. 



Reject all cultures except the agar plates which may be 

 kept until the next exercise for further observation before 

 rejecting. (These cultures should be put in charge of the 

 instructor who will see that the .spores are destroyed before 

 the tubes are cleaned). 



Inoculate a set of media with Bacterium diphtheriae, for 

 study at the next exercise. 



