CURRENT LITERATURE 
NOTES FOR STUDENTS 
Formation and translocation of carbohydrates in plants.—In a series of 
three papers from the Rothamsted Experimental Station, Davis, DatsH, and 
SAWYER * ?, 3 have reported the results of an investigation designed to test 
the validity of BRown and Morris’ conclusion that cane sugar is the primary 
photosynthetic product in foliage leaves, that the dextrose and levulose present 
are products of its hydrolysis, not its precursors, and that levulose is found in 
excess in the leaves and leaf stalks for the reason that dextrose is more readily 
utilized in respiration. The introductory review of literature presents an 
account of work done in this field since the appearance of the memoir by BRowN 
and Morris in 1893. The workers who have given attention to the subject 
since that time fall into three groups: WENT, STROHMER, STEPHANI, PEKLO, 
and Parktn, who adhere to the view that saccharose is the first sugar formed 
levulose are formed simultaneously in the leaf and transported as such to the 
storage organs, where conversion of the reducing sugars into saccharose sub- 
sequently occurs. 
The authors made analyses of leaves, midribs, and upper and lower halves 
of petioles of Yellow Globe mangold at three stages of growth: an early stage 
(August 26) when leaf formation was predominant, the seeds having been sown 
June 9; an intermediate stage (September 10) when leaf growth had practically 
ceased and storage of sugar in the root had attained its maximum rate; and a 
final stage (October 11) when growth of roots had been practically completed. 
Samples were collected at intervals of 2 hours over a 24 hour period on each 
* Davis, Wiii1aAM A., sae ARTHUR JoHN, and SAwyER, GEORGE CONWORTH, 
Studies of the formation an nslocation of carbohydrates in plants. I. The car- 
bohydrate of the mangold ey agro Agric. oc 7: 255-326. aida 
? Davis, Wittia A., Studies of the f 
in plants. II. The Gistie bodions ratio in the mangold. Jour. Agric. Sci 7: 
327-351. 1916. 
3 Davis, Wii1aM A., and Sawyer, GEORGE ConwortH, Studies of the formation 
and translocation of carbohydrates in plants. III. The carbohydrates of the leaf and 
leaf stalks of the potato. The mechanism of degradation of starch in the potato. 
Jour. Agric. Sci. 7:352-384. 1016. 
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