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same time a great botanist and a great teacher, said that he could undertake to illustrate the fundamental principles of his science with the aid of a dozen plants, judiciously selected, and that it was his unvarying practice to induce students to make a thorough study of a few minor groups of plants, in all their relations to one another, rather than to attempt to gain a superficial acquaintance with a large number of species."
The most discouraging parts of Botany to the new beginner consist either in the numerous new and strange names one has to learn the meaning of, or in the minuteness of the parts by which plants are distinguished from each other, or in the great multitude of species of which the vegetable kingdom consists; and it must be confessed that there is something seriously alarming in the mass of preliminary knowledge which it would appear has to be acquired before any perceptible progress can be made.
But if we look at the subject a little more closely we shall find that of the technical terms employed only a small number is really necessary in the beginning; that minute parts are little consulted in practice, however much they may be in theory; and that in consequence of the perfect arrangements of botanists, no more inconvenience is experienced from the number of species than in any other branch of natural history.
There are certain terms, the exact meaning of which must be understood, and which cannot be dispensed with if the science is to be studied to any good purpose; a sort of habit of observation has also to be acquired, without which the differences between one plant and another can never be appreciated or remembered; but these things may be gained imperceptibly and without any extraordinary exertion, either of industry or patience. We have only to begin with the beginning, and never to take one step till that which precedes it is secured; afterwards the student may advance to what point he pleases. This appears to us the only secret in teaching Botany.
We must, however, be careful while we attempt to strip the study of its difficulties, that we do not also divest it of its interest, and imitate those who, by the ingenious substitution of words for ideas, have cont ved to convert one of the most curious and interesting of all sciences into a meager and aimless system of names.
In strict accordance with this method, we proceed now to consider the floral parts of the Buttercup, and their relative position on the receptacle.
You need not be told that plants have generally five very distinct parts, viz: Root, STEM, LEAF, Flower and Fruit. The application of the three first of these terms is already well known to you; the last is applied by botanists not only to such objects as apples, pears, cherries, and the like, but also to any part which contains the seed, so that the grains of corn, the heads of poppy, the nuts of the filbert, and even the little bodies which are commonly called caraways, are all different kinds of fruit.
It is in the flower that the beauty of plants chiefly resides. It is there that we find all the curious apparatus by means of which they are perpetuated, and it is the spot where the greatest number of parts are found, the names of which are unusual and require to be remembered. To illustrate these, let us take a very common plant, to be found everywhere, by the learned called Ranunculus, by the layman, Buttercup, or Crowfoot.
On the outside of the flower of this plant, about the middle of its stalk, are one or two little leaves, which look like the other leaves, only they are a great deal smaller; indeed they are so small as to resemble scales. These are the BRACTS.
Next them, and forming the external part of the flower itself, are five small greenish-yellow hairy leaves (a,b), which are rather concave, and fall off shortly after the flower opens. Leaves of this sort form the Calyx, and are called SEPALS; they protect the more tender parts of the flower.
Next the sepals are placed five other leaves, which are much larger and of a bright, shining yellow. They stand up and form a little cup, in the bottom of which the other parts of the flower are curiously arranged. These five shining leaves form the COROLLA, and are called PETALS. Their business is, in part, to prepare the honey which exudes from a little scale you will find on their inside, near their base (fig. 1), and which, if secreted in sufficient quantity, is collected by bees for their sweet food; and it is, in part, to protect from injury the delicate organs which lie in their bosom. These last are of two sorts, as you will soon learn.
In a ring from which both the sepals and petals arise, you will find a number of thread-like yellow bodies, which are thicker at the top than at the bottom. They spread equally around the center as if they wished to avoid that part, and are a great deal shorter than the petals; we call them STAMENS. Their lower part, which looks like a thread, is called the FILAMENT; their upper thickened end is named the ANTHER. This last part is hollow, and will be found, if you watch it, to discharge a small quantity of yellow powder, called the POLLEN. The pollen has a highly curious office to perform.
Next to the stamens, and occupying the very center of the flower, are a number of little green grains, which look almost like green scales. They are collected in a heap, and are seated upon a small elevated receptacle (figs. 3 and 6); we call the whole collection of them the PISTIL, and each separate one a CARPEL. They are too small to be readily seen without a magnifying glass; but if they are examined in that way you will remark that each is roundish at the bottom, and gradually contracted into a kind of short, bent horn at the top; the rounded part (fig. 4, a) is the OVARY; the horn (6) is the STYLE; and the tip of the style (c), which is rather more shining and somewhat wider than the style itself, is named the STIGMA; so that a carpel consists of ovary, style and stigma. At first sight you may take the carpels to be solid, and fancy them to be young seeds; but in both opinions you would be mistaken. The ovary of each carpel is hollow (fig. 5), and contains a young seed called an OVULE (fig. 5, d), or little egg; so that the carpel, instead of being a seed, is the part that contains the seed.
Although the ovule is really the young seed, yet it is not always certain that it will grow into a seed; whether or not this happens depends upon the pollen, of which we have already spoken, falling upon the stigma. If the pollen does fall on the stigma, it sucks up the moisture it finds there, swells, and finally each of the minute grains, of which it consists, discharges a jet of matter upon the stigma, which fertilizes the ovule, and then the latter grows and becomes a seed. But if the pollen does not fall upon the stigma, then the ovule withers away, and no seed is produced. Thus you see every one of the parts of the Aower is formed for some wise purpose.
You have now seen all the parts of which flowers usually consist; the fruit is merely an alteration of the carpels, and the seed of the ovules. The fruit of the Buttercup is almost exactly the same when ripe as when young, except that its parts are larger, and it has become brown, dry and hard (fig. 6). Separate, at this period, one of the carpels from the remainder, and place it under a magnifying glass. The inside of the carpel is filled up with the seed now arrived at its perfect state; the shell of the carpel has become hard and thick, and not only effectually protects the seed from harm (fig. 8, a), but keeps it in the dark, another wise provision, for without darkness the seed could not grow. The shell thus altered is called the PERICARP.
If you cut the seed through, you will, for a long time, discover nothing but a solid mass of white flesh, in which all the portions seem to be alike; but if you happen to have divided it accurately, from top to bottom, cutting through both edges of the grain as at fig. 8, you will then be able to discover near the base of the seed a very minute oval body (fig. 8. a), which may be taken out of the flesh with the point of a needle. This oval body is a young plant—it is the part which grows when the seed germinates, and is named the EMBRYO; the fleshy matter that surrounds it, called ALBUMEN, is only intended to nourish the young and delicate embryo when it first swells and breaks through the shell. Small as is the embryo, so small as to be invisible to the naked eye, it also is constructed in a regular manner. It is not merely an oval, fleshy body, but it bas two differently organized extremities, of which the one is divided into two lobes, called COTYLEDONS (fig. 10), or seed-leaves, and the other is undivided, and called RADICLE. The latter is the beginning of the root, as the former are the beginnings of leaves. Let the seed fall upon the earth; the embryo imbibes moisture, swells and shoots forth into a young plant.
Such is the structure of a perfect flower, and such the principal terms which you have to remember in order to understand the language of botanists.
By far the greater part of the characters which we have seen that the Buttercup possesses, will be also found in other and extremely different plants; but there are two characters which are what we call essential—that is to say, such as will