52 



THE COLOURS OF FLOWERS. 



are bell-shaped, and each contains a pistil and fi\'e 

 stanaens, like any other perfect flower. But the outer 

 florets are generally sterile ; and instead of beino- 



Mi(/^:,. 



Fig. 17.— Flower of corn bluebottle {s:entaurea cyanus); highest type of cynaroid 



composite ; bright blue. 



bell-shaped they are split down one side and unrolled, 

 so as to form a long ray ; while their corolla is at 

 the same time much larger than that of the central 



