1914) 
COOLEY—SCLEROTINIA CINEREA 307 
of isolation three different methods were employed in preparing 
cellulose from plums, the resulting products being designated, 
for convenience in reference, respectively as soda cellulose, 
washed cellulose, and potassium chlorate cellulose. 
In the preparation of soda cellulose ripe plums were squeezed 
through cheese cloth and the pulp was washed thoroughly with 
water. The pulp was then treated with an 8 per cent solution 
of sodium hydroxide and heated in the autoclave аё ten pounds 
pressure. After thoroughly washing the pulp with water the 
heating with alkali was repeated and the product given final 
washings until free from alkali. 
The second method of isolating cellulose—washed cellulose— 
consisted in washing the fruit pulp with water until free from 
substances soluble in cold water. Water was then added and 
the mixture heated in the autoclave at 15 pounds pressure, 
and washed. Тһе operation was repeated as long as any water- 
soluble substances could be detected. This method, of course, 
gives an impure cellulose, yet the product is one that is free from 
water-soluble substances. 
The third method consisted in oxidizing, dissolving, and wash- 
ing out the plum pulp until a pure cellulose—potassium chlorate 
cellulose—was obtained. Pulp, secured from ripe plums in 
the manner stated above, was washed with cold water until 
the wash water was free from solutes, and then treated with a 
cold solution composed of 30 grams of potassium chlorate dis- 
solved in 520 ce. of cold nitric acid (sp. gr. 1.1). This mixture 
was kept in the ice box for about three weeks, at the end of 
which time the pulp was entirely white. This method! is said 
to yield a product that differs only very slightly from the original 
cellulose. 
The product obtained by these various methods was not al- 
lowed to dry, for it is possible that drying changes the nature 
of cellulose so that it is more resistant to the action of cytolytic 
enzymes. А part of the cellulose obtained by each of the pre- 
ceding methods was treated with Schweizer’s reagent and pre- 
cipitated with hydrochloric acid and washed as stated above 
under the preparation of filter-paper cellulose. These three 
cellulose preparations thus treated with Schweizer’s reagent, as 
1 Fowler, G. J. Bacterial and enzymatic chemistry. 159. 1911. 
