In Pharbitis seedlings, aging is associated with definite trends in the pattern of flowering of the axillaries: 1) the locus of maximum flowering is displaced continuously upward, 2) there is a continuous loss of responsiveness to induction from the base of the plant, upward, 3) flowering of the axillaries is suppressed in general when the terminal bud fails to flower, and 4) flowering at the distal nodes regresses when the terminal bud fails to flower. Phenomena 1 and 2 start at the base of the plant and move progressively upward, whereas 3 and 4 are tied to the possibly rhythmic responses of the terminal buds to floral induction, with aging. Buds at axils that form after induction are capable of flowering. Buds at nodes that flower maximally range in development from those not visible with a stereomicroscope to those with enlarging apices ready to form the first leaf primordia at the time of induction. Axillaries that have formed leaf primordia fail to flower in response to one inductive night.

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