. Botany all the year round; a practical text-book for schools. Botany. 176 BUDS AND BRANCHES 325.—Opposite- leaved twig of horse-chestnut. ing all the points that'were brought out in the examination of your previous specimen. Which is the larger, the lateral or the terminal bud ? (If lilac is used, there will probably be no terminal bud.) Is their arrangement alternate or opposite ? What was the leaf arrangement.'' Count the dots in the leaf scars; are they the same in all} If all the buds had developed into branches, how many would spring from a node.'' Look for the rings of scars left by th
. Botany all the year round; a practical text-book for schools. Botany. 176 BUDS AND BRANCHES 325.—Opposite- leaved twig of horse-chestnut. ing all the points that'were brought out in the examination of your previous specimen. Which is the larger, the lateral or the terminal bud ? (If lilac is used, there will probably be no terminal bud.) Is their arrangement alternate or opposite ? What was the leaf arrangement.'' Count the dots in the leaf scars; are they the same in all} If all the buds had developed into branches, how many would spring from a node.'' Look for the rings of scars left by the last season's bud scales. Do you find any twig of more than one year's growth, as measured by the scar rings ? Look down between the forks of a branched stem for a round scar. This is not a leaf scar, as we can see by its shape, but one left by the last season's flower cluster. The flower, as we all know, dies after perfecting its fruit, and so a flower bud can not continue the growth of its axis, as other buds do, but has just the opposite effect and stops all further growth in that direc- tion. Hence, stems and branches that end in a flower bud can never develop either excurrent or ordinary dehqvtescent growth, but are characterized by short branches and frequent forking. The same thing happens when, for any reason, the terminal bud is destroyed or injured either artificially, or through natural processes, as in the lilac, where it is frequently aborted and its place usurped by the two nearest lateral ones, which put forth on each side of it and continue the growth of the branch in two forks instead of a single axis. This gives rise to the kind of branching which we see exemplified in the lilac, buckeye, horse-chestnut, dogwood, jimson weed, etc., designated by botanists as dicliotomous, or two-forked. Draw a diagram of the buckeye, or other dichotomous. 326.— Diagrams of dichot- omous Please note that these images are extracted from scanned page images that
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