CHAPTER IV.

REPRODUCTION-HOW IT BEGINS.

In preceding chapters we have studied the anatomy of the reproductive organs, and have learned something about their functions. We have learned that little babies are brought into existence by these organs, but we have not studied the exact plans by which this great work is accomplished. We have seen that trees reproduce themselves by bearing acorns, nuts, and other seeds, and that flowers are reproduced in the same way. But just how the acorns and seeds begin their existence, is a subject that we have not yet considered. Neither have we seen how a baby's life begins. In this chapter we will attempt to investigate that branch of our subject, and the better you understand the preceding chapters, the easier will this investigation be.

SEXUAL ORGANS OF PLANTS.

We have seen that animals are either males or females. A careful study of flowers shows that they too are sexed; or rather, that they are the

sexual organs of the plant which produced them. The little stems in the center of a flower are not the same in flowers of different sexes. Those of the male flower are adapted to perform one function, and those of the female another. In the male flowers they are called stamens; in the female, pistils.

POLLEN-FERTILIZATION.

In order that reproduction may take place, that a new life may begin, it is necessary that something from the male sexual organs shall be deposited in the female sexual organs. In flowers, this is a yellow dust called pollen. The pollen grows on the stamens of male flowers, and is conveyed in some way to the pistils of the female flowers. It is usually done by the wind or by bees. In some flowers we find both stamens and pistils, both male and female sexual organs. It is then a very easy matter for the wind to shake the pollen from the stamens, so that it will fall upon the pistils. Or the bees moving about in the blossom searching for honey will rub against the pollen and get it on their wings and legs and bodies, and then rub against the pistils, leaving them part of the pollen. They soon fly to another blossom, carry a part of the pollen with them, and leave a supply on its pistils. A great scientist has said that flowers are bright and pretty

when the pollen must be carried by the bees from male to female flowers; and that Nature gives the flowers these bright hues so that the bees can easily find them. When the wind alone will properly carry the pollen it is produced by stamens that are not associated with pretty flowers. Depositing in a female flower the pollen from a male flower, is called fertilizing it.

When the work is accomplished

the flower is said to be fertilized.

In corn, the tassel is the male sexual organ, and the silk is the female sexual organ. The corn is fertilized by the pollen from the tassel falling upon the silk of the ear. If no pollen should reach the silk, there would be no grains of corn on the cob. If pollen from the tassels of two or more different kinds of corn should fall upon the silk of one ear, there would be a mixture of as many different kinds of corn as there were different kinds of pollen.

It is

The two kinds are

There is one very prolific kind of strawberry that produces very few if any male blossoms. fertilized from other varieties. planted near together, so that the pollen from the male flowers of the variety which produces it in abundance, can easily reach the blossoms of the other variety.

FERTILIZATION IN PLANTS AND
ANIMALS SIMILAR.

Some flowers are fertilized only by the bees; some by the wind only, others by both methods; while others, like the corn, require neither. The different parts being so arranged that the pollen will fall to the proper place without any assistance. Thus we find great variety in the form and arrangement of the sexual organs in different kinds of plants, and many different methods by which the fertilizing is accomplished. This is equally true in the animal kingdom. But the same great laws control reproduction in all of these different departments of nature, notwithstanding the great variety of methods by which they are executed. In both the animal and vegetable kingdoms something must be furnished by the female, and this must be fertilized by something from the male. In the animal kingdom an egg is furnished by the female and it is fertilized by the seed from a male. In some animals the egg is fertilized before it leaves the body of the female. In others, afterwards.

DIFFERENT METHODS OF FERTILIZING THE OVA
OF ANIMALS.

The female fish deposits her eggs in the water and the male fish then fertilizes them by depositing his seed among them. The eggs of birds, horses,

cattle, and all the higher animals are fertilized while yet in the body of the female. The eggs or ova of the higher animals, including human beings, are fertilized by the semen of the male, which is deposited in the vagina of the female, where it can pass into the womb and thus reach the ova.

You will remember how the ova are developed by the ovaries, and how the semen is manufactured by the testicles, and will now be better able to understand and appreciate the wonderful work done by these wonderful organs of reproduction.

After a blossom is fertilized, the leaves soon fall off, and the seeds begin to grow and gradually develop until they are fully matured, when they are capable of sprouting and growing into other plants like their parent plant.

But what is a seed, and how does it grow? That is a question that we have not yet studied, but it is one of importance to us, as an understanding of this will assist us in comprehending how the ovum of a woman assists in developing a baby, all of which will be explained in the next chapter.