CHAPTER XVIII 

 THE FLOWER — ITS PARTS AND FORMS 



The function of the flower is to produce 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 add to the joy of living, 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 

 that are directly concerned in the production of seeds, and 

 those that act as covering and protecting organs. The 

 former parts are known as the essential organs; the latter 

 as the floral envelopes. 



Envelopes. — The floral envelopes usually bear a close 

 resemblance to leaves. These envelopes are very com- 

 monly 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. 173. f^,, 173. _ flower of 



The inner series, known as the a buitercup in sec- 

 coroUa, is usually colored and more 

 special or irregular in shape than the calyx. It is the 

 showy part of the flower, as a rule. The corolla is the 

 second or large whorl in Fig. 173. 



The calyx may be composed of several leaves. Each 

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

 divided, in which case the divisions are called calyx-lobes. 



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