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Table of Contents

Dehiscent Fruits

1. Pod. 2. Siliqua. 3. Silicula. 4. Follicles(cluster of three). 5. Capsule splitting longitudinally. 6. Capsule splitting transversely. 7. Capsule splitting by pores.

After the ovules have been impregnated by the pollen they develop into seeds, each of which consists of or contains an embryo plant; and, at the same time, the ovary itself enlarges, changing its character more or less, till it becomes a ripened fruit.

Fruits vary very considerably in their general characters, but may be divided into two main groups—those that split when ripe (dehiscent fruits) and those which do not split (indehiscent fruits).

The principal forms of dehiscent fruits are:—

1. The pod or legume, which splits into two valves, with placenta on one side.

2. The siliqua, a long, narrow fruit that splits into two valves which separate from a membrane with placenta on both sides.

3. The silicula, of the same nature as the siliqua, but about as broad as it is long.

4. The follicle, which splits on one side only, through the placenta.

5. All other fruits that split are termed capsules. Some of these split longitudinally, some transversely, and others by forming pores for the escape of the seeds.

The chief kinds of indehiscent fruits are:—

1. The drupe or stone-fruit, which consists of a hard stone surrounded by a fleshy covering, as the plum and the cherry.

2. The berry, which is soft and fleshy, and contains several seeds, like the currant and the grape.

3. The nut or achene—a fruit with hard and dry walls, as the filbert and the acorn.

4. The samara or winged fruit, like that of the sycamore.

Various modifications of these indehiscent fruits are to be met with; thus, the blackberry is not really a berry, but a cluster of little drupes formed from a single pistil of many carpels. A berry, too, may be made up of many parts, as is the case with the orange. The apple and similar fruits consist of a core (the true fruit) surrounded by a fleshy mass that is produced from the receptacle of the flower; and the strawberry is a succulent, enlarged receptacle of the flower, with a number of little achenes (the true fruits) on its surface.

The seed, as we have already observed, is the embryo plant. It consists of one or more seed-leaves or cotyledons, a radicle or young root, and a plumule or young bud. In many cases the skin of the seed encloses nothing more than the three parts of the embryo, as named above; but it sometimes contains, in addition, a quantity of nutrient matter in the form of albumen, starch, oil, gum, or other substance.