98 ELEMENTAEY AGRICULTURE 



called carbon, from the air, but the othef parts come 

 to the leaves through the root hairs. The leaves 

 also give off to the air all the water that is not 

 needed by the plants. If the leaves give off more 

 moisture than the roots supply, as they often do on 

 very hot days, the plant wilts in order to prevent 

 further evaporation. 



The Flower. The starch and sugar made by the 

 leaves is either stored up for food or used at once 

 to build plant tissue. When enough has been stored, 

 the plant begins to flower. The flower is sometimes 

 beautiful like the apple blossom, but often, as in 

 the wheat or oats, it is not showy. 



The Seed. The flower of plants has a very im- 

 portant work to do, because it contains the parts 

 which create the fruit. The fruit contains the seeds 

 from which new plants may be grown. If the flower 

 fails to do its work, there will be no fruit, no seeds. 

 and no new plant, unless a new plant can be started 

 from a slip or cutting of the old plant. 



The Father and Mother. The flowers of different 

 plants differ very much, but they usually have two 

 parts. One is the ^^pistiP' or mother part, which 

 contains the ovary or seed food. This seed food 

 will not grow into seed unless it receives some pollen 

 or yellow dust that grows on another part called 

 the ' ' stamen. ' ' The seed itself is ^ tiny baby plant 

 all tucked under a good cover with food enough for 

 it to live on until it can send out rootlets into the 

 ground. 



