CHARACTER OF BACTERIA 21 



atmosphere of air from which the oxygen has been ab- 

 stracted by means of chemicals. 



Demonstration. — IMoldj^ pieces of bread. A throat culture on 

 Loffler serum, one or two days old. Teeth scrapings, under a cover- 

 glass and magnified, unstained. Hanging-drop preparation, prefera- 

 bly of a motile organism (hay bacillus). Be careful that the ob- 

 jective of the microscope is not pushed through the cover-glass. 

 Spores (an old culture of hay baciUi). 



