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 colours contribute 

 to this supreme end. These forms and colours 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 orgmis. 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. ^ig. 173. -Flower of 



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

 tion. 

 corolla, IS usually coloured 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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