CHAPTER XVIII 

 THE PARTS OF THE FLOWER 



249. The flower exists for the purpose of producing 

 seed. It is probable that all its varied forms and colors 

 contribute to this supreme end. These forms and colors 

 please the human fancy and make living the happier, but 

 the flower exists for the good of the plant, not for the 

 good of man. The parts of the flower are of two general 

 kinds — those which are directly concerned in the produc- 

 tion of seeds, and those which act as covering and pro- 

 tecting organs. The former parts are known as the essen- 

 tial organs ; the latter as the floral envelopes. 



250. ENVELOPES. — The floral envelopes usually bear a 

 close resemblance to leaves. These envelopes are very 

 commonly of two series or kinds — the outer and the inner. 

 The outer series, known as the calyx, is usually smaller 

 and green. It usually comprises the outer cover of the 

 flower-bud. The calyx is the lowest 

 whorl in Fig. 187. The inner series, 



known as the 

 corolla, is usually 

 colored and more 

 special or irregular 

 in shape than the 



187. Flower of a buttercup ^alyX. It is thc 



in section. showy part of the ^^^- ^^°^'''" "^ buttercup. 



flower, as a rule. The corolla is the second or large 

 whorl in Fig. 187. It is the large part in Fig. 188. 



251. The calyx may be composed of several leaves. 

 Each leaf is a sepal. If it is of one piece, it may be 



(122) 



