884. The berry.—In the true berry both exocarp (including mesocarp) and endocarp are fleshy or juicy. Good examples are found in cranberries, huckleberries, gooseberries, currants, snowberries, tomatoes, etc. The calyx and wall of the pistil are adnate, and in fruit become fleshy so that the seeds are imbedded in the pulpy juice. The seeds themselves are more or less stony. In the case of berries, as well as in strawberries, raspberries, and blackberries, the fruits are eagerly sought by birds and other animals for food. The seeds being hard are not digested, but are passed with the other animal excrement and thus gain dispersal.
[V. Reinforced, or Accessory, Fruits.]
When the torus (receptacle) is grown to the pericarp in fruit, the fruit is said to be reinforced. The torus may enclose the pericarps, or the latter may be seated upon the torus.
Fig. 478.
Fruit of raspberry.
885. In the strawberry the receptacle of the flower becomes larger and fleshy, while the “seeds,” which are akenes, are sunk in the surface and are hard and stony. The strawberry thus differs from the raspberry and blackberry, but like them it is not a true berry.
886. The apple, pear, quince, etc.—In the flower the calyx, corolla, and stamens are perigynous, i.e., they are seated on the margin of the receptacle, or torus, which is elevated around the pistils. In fruit the receptacle becomes consolidated with the wall of the ovary (with the pericarp). The torus thus reinforces the pericarp. The torus and outer portion of the pericarp become fleshy, while the inner portion of the pericarp becomes papery and forms the “core.” The calyx persists on the free end of the fruit. Such a fruit is called a pome. The receptacle, or torus, of the rose-flower, closely related to the apple, is instructive when used in comparison. The rose-fruit is called a “hip.”
887. The pepo.—The fruit of the squash, pumpkin, cucumber, etc., is called a pepo. The outer part of the fruit is the receptacle (or torus), which is consolidated with the outer part of the three-loculed ovary. The calyx, which, with the corolla and stamens, was epigynous, falls off from the young fruit.
[VI. Fruits of Gymnosperms.]
The fruits of the gymnosperms differ from nearly all of the angiosperms in that the seed formed from the ripened ovule is naked from the first, i.e., the ovary, or carpel, does not enclose the seed.