No attempt has been made in the following chapter to acquaint the student with every term that it is possible to use in describing the organs of a plant; but enough have been explained and used throughout the book to give a comprehensive vocabulary of the subject and to lead one up to the enjoyment of an altogether scientific work on botany.
The existence of the plant and that of the animal are so closely linked together that it would be rather difficult to prophesy the fate of one were the other to withdraw itself from the earth. It is a pleasure to see that they seldom encroach upon each other's mission in life; but are generously helpful by the most amicable arrangements.
The plants absorb from the atmosphere carbonic-acid gas, which, unless this were so, would become abundant in the air and be injurious to animal life. They exhale oxygen, which is the animal's necessary food. The opposite course is pursued by animals. They inhale oxygen and exhale carbonic-acid gas. In this way they return the plants' compliment: by taking from them what they do not want and giving them as food what they do want.
Again, plants are almost altogether dependent upon animal life to perform for them the service of cross-fertilization, page 7. The birds, the butterflies and Master Bee and his family are all ceaselessly busy as their messengers. But there is nothing mean about the flowers. In return, they are quite aware of, and cater to, the tastes of all. When a bird carries the seeds of a flower to some distant place and deposits them, it is only a slight remuneration for the delicious luncheon of red berries that he has enjoyed. If Master Bee follows the road that is plainly marked for him by a deep, rich veining and sips to satiety of a gland of nectar; it is but fair that the anthers shOuioytoad him well with a cargo of pollen to carry off to the pistil of another flower. In fact, as we become more friendly with the flowers we will cease to look upon them so much as luxurious creatures but rather as those that have solved the deep problems of domestic economy.
The plant's individual mission in life is the reproduction of itself.
The flower and its products, the fruit and the seeds, are the organs of reproduction.
The root, the stem and the leaves are the organs of vegetation.
The Inflorescence is the manner in which the flowers are arranged upon the stem.
When but one flower grows upon the end of the stem or flower-stalk, it is said to be terminal, solitary.
It is Axillary when the flower, or flowers, grow from the axils of the leaves, or in the angle formed by the leaf, or leafstalk, and the stem. (Fig. i.)
A Pedicel is the individual stalk of a flower borne in a cluster.
A Peduncle is the stalk of a solitary flower, or the general stalk that bears a cluster.
Sessile is the term used when the flowers grow closely to the stem and are without either pedicel or peduncle.
A Raceme is when the flowers grow on pedicels about equally long that are arranged along the sides of a common stalk, (Fig. 2.)
A Panicle is a compound raceme. (Fig. 3.)
A Spike is like a raceme, only the flowers are sessile. (Fig. 4.) A Spadix is a fleshy spike that is usually enveloped by a leaf-like bract called a spathe. (Figs. 5 and 6.)
A Head or Capitulum is a short, dense spike that is globular in form. (Fig. 7.)
A Corymb is a raceme in which the lower pedicels are elongated so that the flowers all reach about the same height. (Fig. 8.)
An Umbel is like a corymb, only the pedicels branch from the same central point, suggesting the ribs of an umbrella. It may be simple, or compound. (Fig. 9.)
A Cyme is a flat-topped inflorescence, differing from an umbel in that its innermost flowers are the first to open. (Fig. 10.)
A Complete flower is one that is provided with the essential organs of reproduction, the stamens and pistil; and the protecting organs, the calyx and corolla. As an example of a complete or typical flower we may take the one illustrated in Fig. 11 and 12.
The Calyx is the lower, outer set of leaves at the base of the flower that rests upon the receptacle, or end of the flower-stalk. It is usually green, but not always. At times we find it brilliantly coloured and conspicuous. (See Fig. 12.)
The Sepals are the leaves of the calyx when it is divided to the base.
The Calyx is gamosepalous when the sepals are wholly or partly grown together.
The Corolla is the next inner and upper set of leaves. It is the alluring part of the flower, and attracts the bees and butterflies to its whereabouts that its pollen may be carried through their agency. (Fig. 12.)
The Petals are the leaves of the corolla when it is divided to the base.
The Corolla is said to be gamopetalous when the petals are wholly or partly grown together.
The Calyx and Corolla are spoken of as parted when they are divided nearly to the base. When they are divided about one-half they are said to be cleft, or lobed. They are toothed when the lobes are very small.