i68 



PLANT BIOLOGY 



particular reference to its structure. The botanical and 

 horticultural conceptions of a berry are, therefore, unlike. 

 In the botanical sense, gooseberries, currants, grapes, to- 

 matoes, potato-balls, and even eggplant fruits and oranges 

 (Fig. 241) are berries; strawberries, raspberries, black- 

 berries are not. 



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. 



Fruits that are formed by the sub- 

 sequent 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 co- 

 here and form one 

 body (Figs. 243, 244). 



FIG. 242. PLUM; exam- 

 ple of a drupe. 



FIG. 243. FRUIT OF RASP- 

 BERRY. 



FIG. 244. AGGREGATE 



FRUIT OF MULBERRY; 



and a separate fruit. 



Each of the carpels or pistils in the 

 raspberry and blackberry is a little 

 drupe, or drupelet. In the rasp- 

 berry the entire fruit separates from 

 the torus, leaving the torus on the 

 plant. In the blackberry and dew- 



