304 



PLANT LIFE. 



m 



cot 



changes produce a fruit like that of the peach or the cherry. 



The pericarp encloses a single seed 

 with delicate brown seed coats whose 

 protective function has been com- 

 -en pletely usurped by the stone (fig. 

 352). In other cases, while the 

 inner face becomes stony, the outer 

 becomes fibrous, tough, and dry, as 

 in the almond, walnut, and hickory 

 nut. The outer part in the last even 



FIG. 352. Fruit of the cherry, breaks regularly into four pieces. 



halved, e, epidermis of peri- , 



carp; m, fleshy layer of Such fruits furnish a transition from 



pericarp ; en, stony layer of 



pericarp; s, seed; cot, one the lllOSt perfect flCShy frllltS tO the 



of the pair of thickened seed- . 



leaves of embryo. Natural dry fruits. In other cases the placentas 



size. After Focke. . 



become very much enlarged, and the 



whole of the pericarp becomes fleshy, as in the tomato. In 

 others the outer part of the pericarp is hard and firm, while 

 the inner becomes pulpy, as in the pumpkin and squash. 



412. Accessory fruits. --Parts adjacent to the carpels, 

 either flower leaves or axis or both, stimulated to growth, 

 frequently enter into the formation of 

 fleshy fruits. These may be accompanied 

 by either a fleshy or a dry pericarp. In 

 the wintergreen berry the calyx grows 

 thick and fleshy and surrounds a dry peri- 

 carp, which cracks at maturity (fig. 353). 

 In the strawberry (fig. 287) the torus be- FIG. 353- Fruit of 



wintergreen (Gaul- 



comes greatly enlarged and fleshy, while tkeria proctim- 



. bens), halved, show- 



the minute, one-seeded, dry fruits are ing thin (dry) peri- 

 carp, surrounded by 



scattered over its surface, imitating small thickened fleshy 



calyx. Magnified 



seeds. i he fig has the same parts, with about 2 diam. After 

 the torus concave, instead of convex (fig. 

 289). The apple consists of a fleshy torus carrying at its 

 free end the withered calyx and enclosing the tough, thin 



