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THE CANE.4. Generally those parts of the plant undergoing cellular division containmuch starch and albumen and little sugar; where cellular division is restrictedthe reverse obtains.In the life history of the stalk the following phases are distinguished:—1. In very young parts of the stalk only starch or albumen are present,which are consumed little by little in the formation of cellulose.2. In young, rapidly-growing parts of the stalk, the cane sugar broughtdown by the leaf is inverted, and whereas in the leaf the proportions ofsucrose, dextrose, and levulose were as 4:2:l, in the young joints the proportionsFig. 8.are 8 : 1 : 1. A part of the invert sugar is used up in the formation of fibre,a part unites with the amides to form albumen, and a part is deposited asstarch. In consequence of the inversion, the osmetic pressure is raised andthis tends to favour the absorption of plant food.8. In older joints the sucrose formed in the leaf remains unchangedwhen it reaches the joint and the reducing sugars are used up, partly inTespiration, or, perliaps, are partly by a reverted enayme action converted intosucrose; of the reducing sugars that remain, the dextrose is generally iaexcess.11