The Fascination of Flowers [ 295 



The stigma. The combined stigma, style, and ovary form a 

 complete pistil. 



Also within the flower are 



The stamens. A stamen consists of 



The filament. This is a slender stalk, on the top of which rests 



The anther } which encloses a powder (nearly always yellow) 

 that we know as 



The pollen. The pollen grains are formed by the division of 

 cells within the anther. In our typical flower the pistil and the 

 stamens are surrounded by 



The corolla, composed of petals. This word, meaning "crown," 

 is well chosen, for the corolla is the most beautiful part of the 

 flower. In many flowers it is made up of separate petals; in other 

 flowers the squash flower, for one the petals are joined together 

 and show only as separate points. Then there are still other 

 flowers the petunia and morning-glory are among them which 

 have a corolla all in one piece, without any separation of the 

 petals. In any event, the petals are encircled by 



The sepals. All together, the sepals make up 



The calyx, which serves to protect the flower, especially in its 

 budding stage. The sepals, which are really specialized leaves, 

 vary in size, shape, and number in different kinds of flowers. 

 Often the sepals are green, as on the rose; but sometimes as in 

 the case of the tulip you find them the same color as the petals. 

 On some kinds of plants sepals fall off as soon as the flower opens; 

 on many others roses and apple blossoms, for example these 

 leaves remain even after the seeds have ripened. 



How THE SEED STARTS 



The first step in the development of a seed is for pollen 

 to reach the flower's stigma. The pollen may be blown into the 

 stigma from the anther of some flower. What happens more 

 commonly is that an insect, going from one flower to another in 

 search of nectar, gets pollen on its body and the grains later rub 

 off on a stigma. 



Once a pollen grain has become attached to the sticky surface 

 of the stigma, it quickly forms a tiny tube much like a root hair. 



