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V. H. YOUNG 



glucose sporulate. The dry weight of fungus produced, however, 

 is greatest in series A. The dry weight of the cultures of series 

 B is least while the dry weight of series C is intermediate between 

 the other two. Tests of the hydrolytic power of the enzyme 

 produced by the fungus in each of the three series of cultures 

 reveal no difference whatever between the activity of the enzyme 

 from series B and C, both of which contained inulin, while the 

 amount of hydrolysis from the enzyme of series A is only a little 

 more than one-fourth as great as that caused by the enzyme from 

 series A and B. The results of this experiment show in a very 

 striking manner that glucose has little influence on inulase forma- 

 tion in the concentration used, when inulin is present in equal 

 concentration of carbon atoms. Further, the results for cultures 

 containing only inulin or glucose parallel very closely the results 

 tabulated in tables 2, 3 and 4. The following table shows that 

 glucose is without effect on inulase formation in the presence of 

 inulin in the amounts used. 



A second experiment of the same nature as the above corrob- 

 orates the results of this experiment and also throws light on 

 the lower limits of efficiency of inulin as a stimulus to inulase 

 formation. The essential details of this experiment are described 

 below. 



Cultures were set up as in the previous experiment, according 

 to the equivalent carbon concentration in the following series: 

 viz., series A containing 2% of glucose alone ; series J5 containing 

 1.9% of glucose and inulin, equivalent in carbon content to 0.1% 

 of glucose; series C containing 1% of glucose and inulin equiva- 



