56 



FUNCTIONS OF LIVING THINGS 



ovary and its contents together with any parts of the flower that may 

 be attached to it. The chief use of the fruit to the flower is to 

 hold and to protect the seeds ; it may ultimately distribute them 

 where they can reproduce young plants. 



The Necessity of Fruit and Seed Dispersal to a Plant. - We 

 have seen that the chief reason for flowers, from the plant's stand- 

 point, is to produce fruits which contain seeds. Reproduction 

 and the ultimate scattering of fruits and seeds are absolutely neces- 



The development of an apple. Notice that in this fruit additional parts besides 

 the ovary (o) become part of the fruit. Certain outer parts of the flower, the 

 sepals (s) and receptacle, become the fleshy part of the fruit, while the ovary 

 becomes the core. Stages numbered 1 to 7 are in the order of development. 



sary in order that colonies of plants may reach new localities. It 

 is evident that plants best fitted to scatter their seeds, or place 

 fruits containing the seeds some little distance from the parent 

 plants, are the ones which will spread most rapidly. A plant, if 

 it is to advance into new territory, must get its seeds there first. 

 Plants which are best fitted to do this are the most widely dis- 

 tributed on the earth. 



How Seeds and Fruits are Scattered.- -Seed dispersal is accom- 

 plished in many different ways. Some plants produce enormous 

 numbers of seeds which may or may not have special devices to 



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aid in their scattering. Most weeds are thus started " in pastures 



