oct. is, 1925 Translocation of Food Materials of Wheat Seedlings 733 
of material are used. Plants for each sample were collected on four 
or more different days in order to make a composite sample. The 
samples were ground in a pulverizing mill, often enough so that 90 
per cent would pass through a 100-mesh sieve. The sample was then 
mixed and placed in bottles in a desiccator ready for analysis. 
METHOD OF ANALYSIS 
Duplicate samples which weighed between 1 and 1.5 gms. were 
extracted in a small Soxhlet extractor with anhydrous alcohol-free 
ether. This removed the lipoids and soluble pigments, which were 
determined by evaporating off the ether from the extract and weigh¬ 
ing direct. The residue was placed in a 70° C. oven over night to 
drive off all the ether. The next day the residue was removed from 
the extraction shell to a 500 c. c. Erlenmeyer flask, and extracted in 
a water bath for one-half hour with 150 c. c. of 90 per cent boiling 
alcohol, to which a little calcium carbonate had been added to neu¬ 
tralize any plant acids which might be present. This was filtered 
and washed with 90 per cent alcohol. The extract was then reduced 
in volume under reduced pressure at 50° C., as described by Van Slyke 
( 42 , v. 21), to remove the alcohol. It was then diluted with water, 
clarified with lead acetate, filtered, freed from excess of lead by 
sodium carbonate, again filtered, and made up to 100 c. c. volume; 
50 c. c. were used for the reducing sugar and 50 c. c. for the hydrolyz¬ 
able sugars. 
Reducing sugars were determined by the Munson-Walker method. 
The gas was regulated to bring the solution to boiling in the regula¬ 
tion time by using an oil manometer on the gas line. In this way it 
was possible to have the liquid begin boiling within 10 seconds of 4 
minutes. The reducing sugars were expressed as dextrose from the 
Munson-Walker tables given by Leach {27). 
Total sugars were determined by hydrolyzing the extracts with 25 
per cent HC1.; 5 c. c. of HC1 with 1.25 sp. gr. was added to 50 c. c. of 
extract, and boiled for an hour with a reflux condenser. This was 
neutralized with NaOH. The total sugars were determined by the 
Defren-0 7 Sullivan method, and expressed as dextrose. 
In order to determine the dextrins, the residue from the sugar 
extraction was further extracted with 10 per cent alcohol at a tem¬ 
perature of 50° C. for one-half hour in a water bath. This was car¬ 
ried on in the same bath and while the sugars were being reduced in 
volume at 50° C. The filtered extract was concentrated for the 
removal of alcohol and clarified by the method just given. After 
hydrolysis with 25 per cent HC1 for 1 hour and neutralizing with 
NaOH, the dextrin was determined as dextrose by the Defren- 
O’Sullivan method. 
Starch was determined by boiling the residue from the dextrin 
extraction for 1 minute with 80 c. c. of water, in order to gelatinize 
the starch. After cooling to 38° C., the starch was digested with 
fresh saliva as suggested by Link and Tottingham (SO), until a nega¬ 
tive result for starch was obtained with iodine, then boiled and tested 
again with iodine; if negative, it was filtered, and the solution was 
hydrolyzed with 2.5 per cent HC1 for 13^ hours, then neutralized 
with NaOH. The starch was then determined by the Defren- 
O’Sullivan method and expressed as dextrose. The fresh saliva 
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