496 BOTANY or CROP PLANTS 



case, the pistil is fully developed and the pollen potent, while 

 in those flowerS with reflexed stamens, the pollen is more or 

 less impotent. Flowers without stamens do not occur. 

 Among cultivated European varieties, only perfect flowers are 

 common. This has resulted from selection. 



''^''-cap of 

 Spefals' 



->stamenj 



-nectar 

 ffand 



Pig. 210. — Grape flower, opening. X 20. 



The flowers (Fig. 2 10) are h)^ogynous and regular. The 

 calyx consists of a narrow rim at the base of the flower. The 

 corolla has five united, greenish petals; in the bud, they form 

 a cap (Fig. 210) over the stamens and pistils. When the 

 flower opens, the petals become loosened at the base but 

 remain united by the tips. Stamens are five in number and 



