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particular reference to its structure. The botanical and horticultural conceptions of a berry are, therefore, unlike. In the botanical sense, gooseberries, currants, grapes, tomatoes, potato-balls, and even eggplant fruits and oranges (Fig. 241) are berries; strawberries, raspberries, blackberries are not.

Fig. 242.—Plum; example of a drupe.

A fleshy pericarp containing one relatively large seed or stone is a drupe. Examples are plum (Fig.242), peach, cherry, apricot, olive. The walls of the pit in the plum, peach, and cherry are formed from the inner coats of the ovary, and the flesh from the outer coats. Drupes are also known as stone-fruits.

Fig. 243.—Fruit of Raspberry.

Fig. 244.—Aggregate Fruit of Mulberry; and a separate fruit.

Fruits that are formed by the subsequent union of separate pistils are aggregate fruits. The carpels in aggregate fruits are usually more or less fleshy. In the raspberry and blackberry flower, the pistils are essentially distinct, but as the pistils ripen they cohere and form one body (Figs. 243, 244). Each of the carpels or pistils in the raspberry and blackberry is a little drupe, or drupelet. In the raspberry the entire fruit separates from the torus, leaving the torus on the plant. In the blackberry and dew-