x 12. _fb._ fibro-vascular bundle. _M_, diagram of the flower.]
A cross-section of the stem shows numerous whitish areas scattered
through it. These are the fibro-vascular bundles which in the
monocotyledons are of a simple type. The bulb is composed of thick
scales, which are modified leaves, and on cutting it lengthwise, we
shall probably find the young bulb of next year (Fig. _C_, _b_)
already forming inside it, the young bulb arising as a bud at the
base of the stem of the present year.
The flower is made up of five circles of very much modified leaves,
three leaves in each set. The two outer circles are much alike, but
the three outermost leaves are slightly narrower and strongly tinged
with red on the back, completely concealing the three inner ones
before the flower expands. The latter are pure yellow, except for a
ridge along the back, and a few red specks near the base inside. These
six leaves constitute the perigone of the flower; the three outer are
called sepals, the inner ones petals.
The next two circles are composed of the sporophylls bearing the
pollen spores.[12] These are the stamens, and taken collectively are
known as the "_Androecium_." Each leaf or stamen consists of two
distinct portions, a delicate stalk or "filament" (_D_, _f_), and the
upper spore-bearing part, the "anther" (_an._). The anther in the
freshly opened flower has a smooth, red surface; but shortly after,
the flower opens, splits along each side, and discharges the pollen
spores. A section across the anther shows it to be composed of four
sporangia or pollen sacs attached to a common central axis
("connective") (Fig. _H_).
[12] The three outer stamens are shorter than the inner set.
The central circle of leaves, the carpels (collectively the
"gynoecium") are completely united to form a compound pistil (Fig. 81,
_E_). This shows three distinct portions, the ovule-bearing portion
below (_o_), the "ovary," a stalk above (_st._), the "style," and the
receptive portion (_z_) at the top, the "stigma." Both stigma and
ovary show plainly their compound nature, the former being divided
into three lobes, the latter completely divided into three chambers,
as well as being flattened at the sides with a more or less decided
seam at the three angles. The ovules, which are quite large, are
arranged in two rows in each chamber of the ovary, attached to the
central column ("placenta").
The flowers open for several days in succession, b
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