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. This is not mentioned in the study of
the Horsechestnut bud, because it cannot be proved to the pupils, but the
transition is explained in connection with Lilac, where it may be clearly
seen. The scales of the bud of Horsechestnut are considered to be
homologous with petioles, by analogy with other members of the same
family. In the Sweet Buckeye a series can be made, exhibiting the gradual
change from a scale to a compound leaf. See the Botanical Text-Book, Part
I, Structural Botany. By Asa Gray. Ivison, Blakeman, Taylor and Co., New
York, 1879. Plate 233, p. 116.]

[Illustration: FIG. 13.--Horsechestnut. I. Branch in winter state: _a_,
leaf-scars; _b_, bud-scars; _c_, flower-scars. 2. An expanding leaf-bud.
3. Same, more advanced.]

_The Bud Scale-Scars_. These are rings left by the scales of the bud and