198 



Journal of Agricultural Research voi. xviii, no. 4 



Table II. — Analyses of 10 per cent sugar solutions inoculated with spores of Aspergillus 



niger 



[Twenty-four hours' incubation] 



The flasks each received three drops of chloroform and were returned 

 to the incubator at 45° C, where they remained until analyzed at the 

 end of the 24-hour incubation period. They were frequently shaken to 

 assist in the rupturing of the spore walls. From the results recorded in 

 Table II it will be noted that, as in Table I, the flasks inoculated with 

 sterile water heated to 63° and 100° as well as the sterilized inoculum — 

 spores heated to 100° — polarized about 35.8 and contained about 0.04 

 percent reducing sugars. On the other hand, there was a marked decrease 

 in polarization in the flasks inoculated with 10 cc. of spores heated to 63°. 

 This is shown by the value 31, which represents a total loss of 4.6 or a 

 decrease of 1.16 per cent sucrose. The reducing sugars increased appre- 

 ciably to 0.15 per cent from 0.05 per cent. Still more striking is the fact 

 that double this quantity of spores (20 cc.) was responsible for a pro- 

 portional decrease in polarization — amounting to 8.4, or a decrease of 

 2. II as compared with the control — and a sHghtly greater increase in 

 reducing sugars. Again a microscopic examination disclosed no signs of 



