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LON A. HAWKINS 
litmus. Several of the flasks containing the xylan and extract of the 
fungus were again boiled as controls. Chloroform was finally added 
to all the preparations as an antiseptic. The flasks were then placed 
in an incubator at a temperature of approximately 30° C. and allowed 
to remain with frequent shaking for the required time. To see whether 
the preparations* were contaminated with microorganisms frequent 
inoculations were made from the mixtures to various culture media. 
No organisms were found. 
The first series of experiments was carried out with six preparations 
for each experiment, all alike excepting that three had been boiled. 
After these had remained in the constant temperature chamber from 
five to eight days they were removed, and the contents of the flasks 
washed into beakers with 95 percent alcohol. Suflicient alcohol was 
added to bring the mixture up to about 80 percent alcohol, thus pre- 
cipitating the unchanged xylan. The mixture was filtered and the 
alcohol evaporated from the filtrate on the steam bath. One pair of 
preparations consisting of one unboiled and one boiled control was 
used for the determination of the furfurol-yielding substance. A 
similar pair was used for the determination of the reducing substance. 
These last were cleared with neutral lead acetate, filtered, the excess 
lead precipitated as oxalate, and the mixture filtered again. The 
sugar was determined in the filtrate, using Allihn's modification of 
Fehling's solution. The dry cuprous oxide was weighed directly. 
The third pair of preparations was usually used for the preparation of 
the phenylhydrazine derivative which will be taken up later. It 
has been shown earlier in this paper that xylose is soluble in 80 per- 
cent alcohol, while xylan is not; also xylose is a reducing sugar, forms 
furfurol when boiled with HCl and reacts with phenylhydrazine to 
form a characteristic osazone. It is apparent then that if the amount 
of alcohol-soluble furfurol-yielding material and reducing substance 
is greater in the unboiled preparation it will be evidence that a pentose 
sugar results from the action of the extract of fungus mycelium upon 
the xylan. This evidence will be strengthened if the phenylhydrazine 
derivative is similar to xylosazone. The results of this series of 
experiments are shown in Table IV. 
The phenylhydrazine derivative was prepared in the usual manner 
in the third unboiled preparation in all the experiments given in 
Table IV. In all cases it proved to be the same, bright yellow needle- 
30 Wiley, H. W., et al. Loc. cit. 
