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Leaves have a gradual increase in the percentage of pentosane 

 throughout the whole life of the rice plant. The percentage of crude 

 fibre in the leaves collected from plat A are not identical with those 

 of, the leaves from plat B. However, a somewhat similar variation 

 can be traced in their percentages ; that is, the percentage of crude 

 fibre increases, (though not to so great an extent), when the plant 

 body is vigorously developing, and slightly decreases during maturation. 

 Therefore the variations of percentage of crude fibre in the leaves 

 and in the stems are dissimilar, (the variation in the stems has been 

 described above) ; and the differences are largely due to the quanti- 

 ties of starch that are produced in these organs. Hoffmeister found, 

 in his investigation on barley and clover, (v. Czapeck : Biochem. d. 

 Pflanz. I Band, p. 6571913), that the crude fibre in the stems 

 increases throughout the life of these plants, and that the leaves lose 

 a part of this substance towards the end of maturity. In the present 

 experiments the same fact is noticed in the corresponding part of 

 the rice plant. From a physiological stand point, it is very interest- 

 ing to note that the absolute amount of pentosane and crude fibre 

 in the leaves reaches a maximum at the time of flowering, and 

 decreases in the later period of maturation. This indicates that a 

 part of the pentosane and crude fibre in the leaves undergoes a 

 chemical change towards the end of the plant's life, in spite of the 

 fact that the carcohydrates, which usually constitute the frame work 

 of the plant, are considered to be rather stable compounds. The 

 results of analysis, which show that the stems and roots may either 

 a slight decrease or a great inclease in the absolute amount of these 

 carbohydrates at maturity, do not confirm the supposed impossibility 

 of a transformation of these carbohydrates into other subttances ; 

 because, if the formation of pentosane and crude fibre takes place 

 more actively than the catabolic function, analysis should indicate 

 that there is only an increase of these carbohydrates and never a 

 decrease. From general physiological considerations, assuming that 



