122 MORPHOLOGY AND LIFE HISTORY 



turbidity and odor. If the instructor deems it 

 advisable, some members of the class, instead of boil- 

 ing the contents of one tube after infection, may put 

 into it ten drops of a 40 per cent, solution of for- 

 maldehyde. 

 E. Reproduction: 



Do you find any bacterial cells that seem to be divid- 

 ing? Is there a tendency for the cells to remain 

 united after division? Read in some standard 

 work on bacteria about the formation of spores. 



