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Typically, a general formula will be used to represent the flower
structure of a plant
family rather than a
particular species. The following representations are used:
CaX
= Calyx (sepal whorl) X = number of sepals (e.g. Ca5
= 5 sepals)
CoX
= Corolla (petal whorl) X = number of petals (e.g., Co3(x)
= petals some multiple of three )
Z
= add if
Zygomorphic
(e.g., CoZ6 = zygomorphic with 6 petals)
AX
=
Androecium (whorl of
stamens) X = number of stamens (e.g., A∞ = many
stamens)
GX
=
Gynoecium (ovary
bearing carpels) X = number of carpels: if one, termed 'monocarpous', if
two or more and free or distinct, termed 'apocarpous', if two or more
and fused, termed 'syncarpous' or connate. (e.g., G1 =
monocarpous)
A floral formula would appear something like this:
Other key used in
Floral Formulas:
CaCo
perianth; if sepals and petals are alike termed 'tepals'.
= adnate; or fusion of two different floral whorls
=
'hypanthium' when all whorls are present. Especially frequent in the
Rosidae. The floral whorls are perigynous to the gynoecium, which is
still considered superior to them.
X - to represent a
"variable number"
∞ - to represent "many"
X - X
= variation in number in that family
X = X
= Like floral parts in two whorls
= fully fused or connate, especially in reference to the carpels of
the gynoecium. If carpel # has no fusion symbol, carpels are free and
distinct.
=
apically fused or connate
=
basally fused or connate
=
fully distinct or fused; variation within a family
= male unisexual flower
= female
unisexual flower
= hermaphrodite bisexual flowers
*
= staminode; a
sterile stamen
 =
ovary inferior to insertion point of the other whorls. The floral whorls
are epigynous to the gynoecium.
= ovary superior to insertion point of other floral whorls. The
floral whorls are hypogenous to the gynoecium.
= ovary inferior to superior - variation exists
For example the floral formula of the Cactaceae Family
is:
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