Fruits Of Tropical Africa
WHEN the pollen passes through the tiny hole in the stigma and down the style to the ovary, the seed or seeds (there
may be one or several) begin to ripen, and then a great change takes place in the
flower. The petals and stamens fade; the ovary containing the seeds, and often the
part of the flower stalk upon which the ovary stands, which is called the receptacle,
grow very rapidly until at length the fruit is formed. Thus a fruit is the ripened
ovary containing the seeds, and sometimes the receptacle as well as the ovary forms part of the fruit Tomatoes, okras, oranges, limes, beans and the black pods of the
flame tree are all fruits, and the seeds are found inside, as you know.
Now why does the plant trouble to form a fruit? Why does it not produce the seeds
direct? The answer is that very young seeds, like very young animals, need
protection at first, and it is not until the seed is quite mature and ready to start and grow
into a new plant that it is set free from the fruit. There are, as you know, a great
many kinds of fruits. An orange is soft and juicy, as are the tomato and the mango;
the coconut is encased in a tough stringy coat or husk; the bean has a pod as have
the seeds of the flame tree, the bauhinia, the pride of Barbados, etc.
The
mango seed is covered with a hard shell with juicy pulp all round it. Fruits may
be dry or succulent; they may be made up of one or of many carpals; there are fruits
which split to let their seed escape, while others do not shed the seed at all and
rot before the seed is freed. Some fruits are formed from a very much enlarged flower
stalk or receptacle, with the seeds arranged all round. Dry fruits may or may not
shed their seeds; the latter are called achenes; zinnias and sunflowers have achenes
as fruits; the fruit of the maize is also achene, and a great many seeds grow together
on m enlarged receptacle. Among the dry fruits which shed their seeds are the pods
of the bean, the flame tree, etc., which are made up of one carpel, and the capsules,
which are made up of several carpals joined together; as examples of capsules we
have the fruits of the lilies, cotton, orchids, teak, etc. The methods of shedding
seed are often very different. For instance, a pod sheds the seed by splitting;
capsules shed their seed in several different ways; sometimes they have a sort of
lid which cracks off when the seed is ripe, or there may be holes in the fruit as
in the poppy; some capsules split lengthwise as in castor-oil, queen flower (Lagerstaemia)
and sandbox Succulent or juicy fruits are also very various.
If the fruit has only one seed contained in a shell and covered, shell and all, with juicy pulp, it is called a drupe; a mango is a drupe. Two familiar African
fruits, the palm nut and the coconut, are drupes. This may seem strange since it
is said above that a drupe is a fleshy succulent fruit; but in structure both the
Coconut and the palm nut
resemble the mango, and in the earlier stages the husk
is indeed juicy, and only dries up later, leaving the stringy fibrous covering of
the ripe fruit The coconut that we buy in the market is the seed, and corresponds
to the stone of the mango; the covering of fiber and the outside golden skin of
this nut correspond to the juicy part and outside skin of the mango. Similarly you
can make out the corresponding parts in the fruit of the oil palm.
Juicy fruits do not shed their seeds, but fall on
the ground and rot. Some fruits
are not formed from a single flower but from many, and the seeds
usually remain
attached to a very much enlarged receptacle; examples of such fruits are the pineapple,
breadfruit, the fig' the Sierra Leone pear, etc. In the pineapple, the juicy part
we eat is the receptacle grown very large, while the seeds and the remains of the
flowers are the little brown spots scattered near the outside. On the other hand,
if a fruit has several seeds covered with a juicy pulp, the fruit is called a berry.
Oranges, limes, tomatoes, cucumber, gourd, guava, etc., are berries.