CHAPTER XXII 

 THE ANAEROBIC GROUP OF BACILLI 



MEMBERS 



Bacillus tetani. 



B. oedematis maligni. 



B. aero genes capsulatus. 



B. anthracis symptomatici. 



B. botulinus. 



And others. 



Study the different methods of anaerobic cultivation in 

 the textbook. 



1. Special study A. Park's method. 



a) Boil three tubes of glucose-agar vigorously for 5 

 minutes, to drive out the dissolved oxygen. (Why is 

 the presence of glucose desirable ?) 



b) Cool to 43 and inoculate from stock-culture of 

 B. tetani, B. oedematis maligni, and B. aerogenes capsu- 

 latus. 



c) Solidify rapidly by immersion in cold water. 



d) Cover the medium with a thin layer of liquid paraf- 

 fin. 



e) Place in thermostat. 



NOTE. The layer of parraffin effectively excludes the atmos- 

 pheric oxygen, which would be inhibitory to the growth of the 

 anaerobes. The oxygen necessary for their multiplication is 

 derived from nutrient material of the medium. 



2. Special study B. Wright's modification of Buch- 

 ner's method. 



a) Liquefy, as before, six glucose-agar tubes, the 

 plugs of which have been replaced by absorbent cotton. 



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