]
The scars on the stem are of three kinds, leaf, bud-scale, and
flower-cluster scars. The pupils should notice that the buds are always
just above the large triangular scars. If they are still in doubt as to
the cause of these marks, show them some house-plant with well-developed
buds in the axils of the leaves, and ask them to compare the position of
these buds with their branches. The buds that spring from the inner angle
of the leaf with the stem are _axillary_ buds; those that crown the stems
are _terminal_. Since a bud is an undeveloped branch, terminal buds carry,
on the axis which they crown, axillary buds give rise to side-shoots. The
leaf-scars show the leaf-arrangement and the number of leaves each year.
The leaves are opposite and each pair stands over the intervals of the
pair below. The same is observed to be true of the scales and leaves
of the bud.[1] All these points should be brought out by the actual
observation of the specimens by the pupils, with only such hints from the
teacher as may be needed to direct their attention aright. The dots on the
leaf-scar are the ends of woody bundles (fibro-vascular bundles) which, in
autumn, separated from the leaf. By counting these we can tell how many
leaflets there were in the leaf, three, five, seven, nine, or occasionally
six or eight.
[Footnote 1: Bud-scales are modified leaves and their arrangement is
therefore the same as the leaves.
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