Page 46 - Pharmacognosy-I (02-06-06-102)

Structure of Corolla:
The petal is a modified leaf, formed of inner and outer

epidermis enclosing a narrow undifferentiated mesophyll,
longitudinally traversed with veins of reduced vascular bundles.

The epidermis resembles that of ordinary leaf, but the cells are
usually with strongly wavy walls and are frequently papillosed, a
condition which gives the velvety appearance to petals. Stomata
are present on both epidermises but in small numbers. The
epidermis of the petals may bear hairs of both glandular and non-
glandular types.

Androecium

The androecium is one of the essential floral organs. It is the
male sexual organ of the flower. It consists of one, two or more
whorls of stamens arranged within or above the corolla.
The complete fertile stamen consists of two parts:
1- Filament: which corresponding to the leaf-stalk and bearing an
apical swollen pollen-producing structure called anther. The anther
may be sessile if the filament is absent.

2- Anther: It is a swollen, pollen-producing structure. It is
divided into two anther-lobes by a structure called connective
which lies on the back of the anther and corresponds to the
midrib in the leaf. Each anther lobe includes two elongated
pollen-sacs containing numerous pollen grains.

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