The practical distinction between oxidation
and fermentation of carbohydrates rests on the
role played by atmospheric oxygen. The degree
of acidity produced by oxidative metabolism is
usually lower than that produced by fermentative
metabolism. Since most bacteria produce
alkaline substances from peptone, the small
amount of acid which may be produced by oxida-
1 Acknowledgment is made to the Standard
Oil Company of Indiana for support of this work
through a fellowship to the senior author.