Getting into botany requires learning a lot of new
terminology and this can be daunting for the beginner. It is best to learn by actually looking at examples of
different flower families and that can be done using common species that can be found in the average garden. All you need for this one is a hand lens and a sharp blade
The scientific name of the snowdrops (Galanthus) is derived from the Greek gala meaning milk and anthos meaning
flower. The species name (nivalis) is Latin for snow.
The flowering plants are divided into two large groups, the monocotyledons and the dicotyledons, referring to the
number of first leaves that emerge from the seed when a plant germinates. This isn’t a helpful distinction to identify
flowers but there are a number of clues that can be seen in the snowdrop that
indicate they are monocotyledons.
- the veins of the leaf are parallel to one another and the leaves are long and thin
- the flower parts are in multiples of three
The snowdrop flower
consists of six white sections that one might call petals - three of them
longer and rounded at the tips and three shorter ones with a notch at the end
outlined in green. In this case the
botanical term perianth segment is used because
you can’t tell whether they are petals or sepals. There
are three longer outer perianth segments and three
shorter inner perianth segments, forming two
whorls. The perianth segments are
attached to the end of the ovary which is
obvious and green. This flower is
described as having an inferior ovary (rather
than superior or half-inferior).
Unfortunately botanists also use another term for the same thing, calling
the flower epigynous (epi = on top of; gynous =
female parts). Both terms refer to the ovary being underneath the other parts of the flower. Inferior emphasises the position of the ovary below the other parts and epigynous emphasises that the other parts of the flower are on top of the ovary. When in bud the flower is enclosed in a
single leaf-like structure termed a spathe.
If the outer perianth segments are removed along with one of
the inner perianth segments and one of the stamens, the other parts of the
flower are visible.
From the centre of the ovary there
is a narrow green style with the tip hardly
differing in structure, termed the stigma. These three structures make up the female
parts of the flower and are collectively called the gynoecium.
Around the style there are six stamens. The stamens are made of a thin white filament which is attached to the base of an orange anther which tapers to a point. The anthers contain the pollen which can be
seen in the photograph, staining the inside of one of the perianth segments and
the stigma. The stamens (anthers +
filaments) are the male parts of the flower and are collectively called the androecium. The
position on the anther where the filaments attach is important. In this case they are attached to the base of
the anther so they are termed basifixed. How the anthers open is also important - the
opening of the anthers to release the pollen is called dehiscence. Here the anthers open by a slit which opens
towards the centre of the flower and this condition is called introrse dehiscence.
If you cut the ovary
through lengthways using a blade the internal structure can be seen. The outside wall encloses hollow sections
which are called locules. These are packed with white ovules which are attached to the central axis of the
ovary. If the ovary is cut across it can
be seen there are three locules. After
the ovules are fertilised they become the seeds
and the ovary becomes the fruit.
- perianth in two whorls of three rather similar segments, both coloured rather than green
- flowers containing both male and female parts
- ovary inferior / flower epigynous
- six stamens
- narrow leaves
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