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Comparative studies of natural groups of organisms

Anther
Petal

Ovary
Sepal
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Thalamus

Figure 3.33: Structure of a hypogynous flower

(b) Perigynous flower free from it; such an ovary is said to be half
In this type of a flower, the margins of inferior. Examples include cherry and rose
the thalamus grow upwards to form a cup flowers. The term “perigynous” emanates
shaped structure called the calyx tube that from the nature in which other floral parts
encloses the ovary. However, it remains appear to enclose the ovary (Figure 3.34).

Anther

Ovary
Petal

Sepal
Thalamus

Figure 3.34: Structure of a perigynous flower

(c) Epigynous flower
In this flower, the calyx, corolla, and Anther
androecium arise above the ovary and Petal
completely enclose it. The ovary is therefore Sepal
said to be inferior, while the rest of the Ovary
floral parts are said to be superior (Figure
3.35). Examples of epigynous flowers
include the cucumber, apple, guava, and
passion flowers.
Figure 3.35: Structure of an epigynous flower

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