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Decapitation of the pea plant resulted in the growth of all the lateral shoots. The initial growth of all lateral buds was somewhat similar. The differential growth rates developed later on. The pattern of growth of lateral shoots varied with the age of the plant when decapitation was performed. The basal shoots dominated when the plants were decapitated at the 2‐leaf stage. At 3‐leaf stage decapitation resulted in the dominance of shoot 5. Decapitation at 4‐or‐more‐leaf stage resulted in the eventual dominance of the suhterminal lateral shoot. As a rule P‐32 moved to the most actively growing part of the plant, i.e. apex in intact vegetative plant, the growing lateral shoots in a decapitated plant, the elongating subapical parts of the stem and the roots. The various metabolic sinks seemed to compete actively for this nutrient, therefore P‐32 accumulation in any particular growing region of the plant was taken as an indicator of nutrient utilization potential of that part. The stem apex of an intact plant seemed to loose its dominance with the increasing age of the plant. The loss of apical dominance was almost complete during the reproductive phase of the plant, during which the upper lateral shoots initiated growth. Their growth, however, was inhibited soon because of competition with the other developing sinks, viz., the flower and the fruit. The amount of soluble carbohydrates in various parts of the pea plant followed essentially the same pattern as did P‐32 accumulation. These distribution patterns were apparently correlated with the growth of the plant.

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In a recent paper, SWANSON and BOHNING (2) These studies have now been extended to include the influence of hypocotyl temperature on the rate of carbohydrate transport from bean leaves, using a similar technical approach.Seeds of Phaseolus vulgaris, variety Black Valentine, were planted in sand and allowed to germinate under greenhouse conditions. As soon as the hypocotyls had straightened, selected seedlings were transplanted to .a culture tray containing a complete culture solution. The plants were individually supported by means of split cork stoppers placed around the base of the hypocotyl. The solution was continuously aerated and the plants were allowed to develop under the prevailing greenhouse conditions until used in the experiments.When the primary leaves were nearly expanded and the distance from the base of the hypocotyl to the primary leaf node was approximately five inches, the plants were transferred to specially constructed temperature jackets mounted above asphalt-paraffin-coated metal trays containing complete culture solution and equipped with carbon tube aerators. Each of these units accommodated 10 plants, and four such units were used in each experiment. A modification was made in some of the later experiments in that in place of the metal trays, the roots of each plant were allowed to develop in aerated culture solution in individual glass tubes. The jackets for temperature control were larger (4" x 44" x 41I") than those used in controlling petiole temperature (2), but afforded the same flexibility and accuracy of control. The temperature of the hypocotyl was varied within the range of 7 to 400 C by means of the jackets while the temperature of the rest of the plant was maintained at 25 ± 10 C.