THE GROWTH OF THE FLOWER INTO FRUIT 425 



the flower is in full blossom the anther sacs open and the pollen 

 grains are exposed. Occasionally pollen is so abundant that 

 it brushes off on the nose when we smell the flower, or it falls 

 on the table and makes a faint dust when we arrange a bouquet. 



In the center of the flower is the pistil (Figs. 289 and 290), hav- 

 ing a swollen base, the ovary, and a broadened tip, the stigma. 

 The ovary is connected with the stigma by a stalk called the style. 

 The stigma is usually covered with a sticky 

 fluid, to which dust and pollen adhere 

 readily. When we open an ovary, we see 

 that it contains tiny seedlike bodies, called 

 ovules. It is the ovary of the flower which 

 develops into fruit, and the ovules which 

 develop into seeds. 



The growth of the flower into fruit. - 

 Seed cannot form and fruit cannot develop 

 unless pollen from an anther falls on the 

 stigma of a similar flower. A cherry can- 

 not form unless the pollen from a cherry 

 blossom falls on the stigma of a cherry 

 blossom ; a cucumber cannot form unless 

 the pollen from a cucumber blossom falls 

 on the stigma of a cucumber blossom. 

 As soon as pollen grains of the right sort fall on a stigma they 

 begin to grow and to send delicate threadlike tubes down 

 through the style to the ovary. The delicate threads enter the 

 ovary, and when they reach the ovules, they burst and discharge 

 a mass of matter. The ovules unite with the discharged matter 

 and are said to be fertilized. The fertilized ovules begin to grow 

 and to require more space, and the ovary wall swells and enlarges 

 in order to accommodate them. In time the swollen ovary be- 

 comes a ripened fruit, and the enlarged ovules become ripened 

 seeds. Some fruits, like the cherry, contain only one seed; 



