CHAPTER XI 

 FRUITS; SEEDS AND SEEDLINGS; SEED DISTRIBUTION 



146. Origin of the fruit. As already suggested (sect. 127), 

 the ovary, after fertilization, enlarges and develops into some 

 kind of seed-containing structure. An apple, a bean pod, and 

 a tomato are good examples of matured ovaries (with or with- 

 out the addition of other parts) serving to contain the seeds, 

 and each is botanically termed a fruit. Most of the fleshy 

 portion of the apple is derived from the enlarged receptacle 

 and calyx, though a little of it about the core comes from 

 thickening of the walls of the carpels. The papery chambers 

 of the core, with the contained seeds, are the most important 

 portion of the apple for reproduction ; that is, for growing new 

 apple trees. A ripe bean pod with its seeds is a dry fruit 

 resulting from the maturing of a one-loculed ovary and its 

 contents ; a ripe tomato is a fleshy fruit resulting from the 

 maturing and extensive thickening of a two-to-several-loculed 

 ovary and its contents. 



147. Kinds of fruits. The various types of fruits have been 

 carefully classed for purposes of scientific study and descrip- 

 tion, but in an elementary book it is not worth while to give 

 much space to an account of these classes. 1 The fruits most 

 important for human food are the grains dry fruits with the 

 ovary wall so closely adherent to the seed that the whole is 

 usually taken for a seed. Nuts, such as the beechnut, hazel- 

 nut, chestnut, and acorn, are hard, dry, one-seeded fruits, 

 most of them larger than grains and resulting from the ripen- 

 ing of a several-loculed ovary only one chamber of which 



1 Some of the principal types of fruits are admirably described in Gray, 

 Structural Botany. American Book Company, New York. 



156 



