CUP FLOWERS 307 



simple that at first sight we scarcely recognize it as a Cup 

 Flower. The expanded rim below the globular axis is 

 however the beginning of the cup form of the flower axis. 



562. The Spiraea or Bridal Wreath (Spiraea) of the 

 gardens shows a great reduction in the number of carpels, 

 from many (in the Strawberry) to five 



each with several ovules, and with this 



we have the disappearance of the globular 



flower axis, while the fleshy rim or disk FlG ' 181 -~ s P iraea - 



has now become somewhat cup-shaped. On the margin 



of the cup are borne the many stamens, usually 20, in 



whorls of 5 or 10 each, the five separate, white, rounded 



petals, and the five separate pointed, green sepals. 



563. The Rose flower (Rosa) shows a considerable 

 advance over that of the Spiraea in its general structure 

 although more primitive as to its carpels and stamens. 

 The cup is very deep and completely encloses the many 

 free, biovulate (but one-seeded) carpels. The stamens 

 are very many (40-50, or more) in whorls of 5 or 10, 

 attached to the cup margin. The five petals are large and 

 rounded, and with the pointed, green sepals are attached 

 to the margin of the cup. After flowering the cups ri- 

 pen into edible, fleshy "rose-apples." 



FIG. 182. Rosa. . FIG. 183. Malus. 



564. In the Apple flower (Malus) the cup is still 

 deeper, narrower, and more fleshy, and it encloses and is 

 grown to the five, slightly united biovulate carpels. 

 The many stamens, 20 or more, in whorls of 5 or 10 each, 



