1916] 
Emic—Yerast FUNGI 287 
to make up the volume to one liter. This yeast suspension 
was then heated in an Arnold sterilizer at 100°C. for one 
hour. After most of the yeast cells had settled to the bottom 
of the flask, the supernatant liquid was decanted and filtered 
through hard filter paper. This filtrate was then run through 
a Berkfeld cylinder to remove all yeast cells. The acid 
nutrient solutions were made from this last filtrate by the 
addition of 1 per cent citric, 1 per cent lactic, 1 per cent 
malic, 1 per cent succinic, 1 per cent tartaric, and .5 per cent 
acetic acid. 
For the acid reaction 50 се. of the acid nutrient solutions 
in 100-ee. Erlenmeyer flasks were sterilized, and then each 
was inoculated with a pure culture from one of the thirteen 
fungi. After incubation for thirty days at room temperature, 
the solutions were made up to the original volume with dis- 
tilled water. A 10-сс. portion was then titrated with N/10 
caustic soda, phenylphthalein and litmus being separately 
used as indicators. The results given in table п are in terms 
of cubice centimeters of N/10 caustic soda required to neu- 
tralize 10 ce. of the culture solutions. 
