TILE PLANT GROUPS 



91 



only be seen with very high powers in stained prepara- 

 tions. Omit unless such preparations are available. 

 c. Cell division. Do you see any bacteria in which the 

 cells are dividing ? Consult Fig. 135 of the text, and 

 the discussion on vegetative reproduction in bacteria. 



Fi<;. 21. Form types of bacteria 



typs of bacilli; b, types of micrococci; c, types of spirilla. After Williams 

 From Marshall's " Microbiology " 



d. If stained preparations of bacteria are available, 



study the structure and form of bacteria in such 

 preparations. 



e. Drfi"'ti/</x. Draw the form types of bacteria observed. 

 f. Bai'li'r'ia f l]i<- //r///. Scrape the teeth with a sterilized 



needle, or scalpel. Sterili/e first in a flnme or in 

 strong alcohol. Mount and observe. Do you find 

 more than one form of bacterial cell in your prepa- 

 ration? How many do you find? Make a drawing 

 of the bacteria found on the teeth. 



