50 AGRICULTURE 



the sunlight, which is necessary to form chlorophyl, cannot 

 reach them. Bulbs, such as the lily and the onion, are thick- 

 ened, underground leaves crowded together on a shortened stem. 

 Perfect Flowers. The cotton is a plant with a perfect flower, 

 that is, the blossom has calyx, corolla, stamens, and pistil. One 



blossom can fertilize and pro- 

 duce seeds. 



Imperfect Flowers. Some 

 plants have imperfect flowers in 

 which one or more of these four 

 parts is lacking. Some lack the 



Perfect and imperfect strawberry blossoms. Calyx, Or the Corolla, Or both ; 

 The one on the left has both stamens and some bear Stamens and pistils On 

 pistils, the one on the right has pistils only. i_i T\- j 



separate blossoms. Did you ever 



think of the tassels and the ear as the blossoms of the corn? 

 That is what they are. The tassels are the stamen-bearing flowers, 

 and the yellow dust on them is pollen. The ear is the pistil- 

 bearing flower and cannot ripen grain unless pollen falls on its 

 silk, which is the ends of its pistils. Sometimes the pistil- and the 

 stamen-bearing blossoms are on different plants. This is the case 

 with the hop and with many varieties of strawberries. Pistil- 

 bearing flowers cannot bear fruit and mature seeds unless they 

 are fertilized by stamen-bearing ones. Plants which bear only 

 stamens never produce seeds. 



Pollen Carrying. One plant cannot leave its place in the field 

 and carry its pollen to another. How, then, is it conveyed ? The 

 two chief ways are by means of the wind and by means of 

 insects. 



By the Wind. Pollen is so light that it is easily and often 

 carried a great distance by the wind. It is to prevent the wind 

 from bearing the pollen of one to another, that farmers plant dif- 



