the egg and the development of fruit containing seed. Except where
it is terminal it arises, like the leaf-shoot, in the axil of a leaf,
which is then known as a bract. Occasionally, as in violet, a flower
arises singly in the axil of an ordinary foliage-leaf; it is then
termed axillary. Generally, however, the flower-bearing portion of
the plant is sharply distinguished from the foliage leaf-bearing or
vegetative portion, and forms a more or less elaborate branch-system
in which the bracts are small and scale-like. Such a branch-system is
called an inflorescence. The primary function of the flower is to bear
the spores. These, as in Gymnosperms, are of two kinds, microspores
or pollen-grains, borne in the stamens (or microsporophylls) and
megaspores, in which the egg-cell is developed, contained in the
ovule, which is borne enclosed in the carpel (or megasporophyll). The
flower may consist only of spore-bearing leaves, as in willow, where
each flower comprises only a few stamens or two carpels. Usually,
however, other leaves are present which are only indirectly concerned
with the reproductive process, acting as protective organs for the
sporophylls or forming an attractive envelope. These form the perianth
and are in one series, when the flower is termed monochlamydeous, or
in two series (dichlamydeous). In the second case the outer series
(calyx of sepals) is generally green and leaf-like, its function being
to protect the rest of the flower, especially in the bud; while
the inner series (corolla of petals) is generally white or brightly
coloured, and more delicate in structure, its function being to
attract the particular insect or bird by agency of which pollination
is effected. The insect, &c., is attracted by the colour and scent
of the flower, and frequently also by honey which is secreted in some
part of the flower. (For further details on the form and arrangement
of the flower and its parts, see FLOWER.)