The carpels are the chief agents in the formation of the fruit, and they form the endocarp (core), and sometimes the whole pericarp, or seed-vessel. Upon the nature of the various parts and the changes they undergo during the ripening of the seeds the nature of the fruit depends. The fruits are classified, some being the produce of a single carpel, others of several united carpels.
Fig. 795.—Umbelliferous plant and its fruit.
Fig. 796.—Three-celled capsule.
Fruit, in botany, is by no means limited to the juicy products of trees or plants which are so refreshing in the summer weather, and so acceptable in any form. In plant life the herb yielding seed produces a fruit equally with the orange or the apple. The fruit is the outcome of the varied processes of the plant. We may trace the plant from its tiny, sometimes very minute seed, through stem to flower and seed again. “In the final struggle, even when life is hopeless, and starvation, in consequence of drought, is imminent—when all is hopeless and barren, the plant will make an effort to produce its fruit and flower.” This is a very touching and interesting fact in nature—this last attempt to beautify the earth and to propagate its species for the use of man.
Fig. 797.—Poppy.
Fruit, then, is not limited to the market and the stall.
This statement scarcely needs proof; but if we consider for a moment the number of “wild” fruits—the parents, probably, of our table-fruits—we find many we cannot eat. In short, out of the hundred thousand plants which bear flowers scarce one two-hundredth part serve us as producers of edible fruits.