CHAPTER XLII. 



THE FLORAL SHOOT. 



I. The Parts of the Flower. 



THE portion of the stem on which the flowers are borne is 

 the flower shoot or axis, or taken together with the flowers, it is 

 known as the Flower Cluster. 



804 The flower. The flower is best understood by an exam- 

 ination, first of one of the types known as a "complete"' flower, 

 as in the buttercup, the spring beauty, the bloodroot, the apple, 

 the rose, etc. 



There are two sets of organs or members in the complete 

 flower (i) the floral envelope; (2) the essential or necessary 

 members or organs. 



The floral envelope when complete consists of ist, an outer 

 envelope, the calyx, made up of several leaflike structures 

 (sepals), very often possessing chlorophyll, which envelop all 

 the other parts of the flower when in bud ; 2d, an inner envelope, 

 the corolla, also made up of several leaflike parts (petals'), usu- 

 ally bright colored and larger than the sepals. The outer and 

 inner floral envelopes are usually in whorls (though in close spirals 

 in many of the buttercup family, etc.), and for reasons discussed 

 elsewhere (Chapter XXXIV) represent leaves. The essential 

 or necessary members of the flower are also usually in whorls 

 and likewise represent leaves, but only in rare cases is there any 

 suggestion, either in their form or color, of a leaf relationship. 

 These members are in two sets: (i) The outer, or androecium, 

 consisting of a few or many parts (stamens'); (2) the inner set, 

 the gynoecium, consisting of a few or many parts (carpels'). 



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