CHAPTER XXII 

 THE ANAEROBIC GROUP OF BACILLI 



Members — 



Bacillus tetani. 



B. oedematis maligni. 



B. aerogenes capsulatus. 



B. anthracis symptomatici. 



B. botulinus. 



And others. 



Study the different methods of anaerobic cuUivation 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) SoUdify 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 plugs of which have been replaced by absorbent cotton. 



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