DEVELOPMENT OF PLANTS 



469 



Rubiales are an important tropical group and furnish the coffee 

 (Coffea) and the cinchonas which yield such drugs as quinine 

 and calisaya. 



154. Campanulales, the Bellflower Order. — This order marks 

 the culmination of the tendencies that we have seen steadily 

 progressing through the monocotyledons and the dicotyledons. 

 The variations have been of so peculiar and successful a nature 

 that no group of plants are so widely distributed and in the 

 more specialized families of so common occurrence. Over 



Fig. 337. Lower forms of the Campanulales: A, inflorescence of the 

 bellflower {Campanula). B, section of a young flower. The hairy style 

 is pushing up between the encircling anthers and sweeping the spores out 

 of them. Note the closed stigmatic lobes. C, older flower. The anthers 

 are withering and the stigmas are curving back towards the spore-covered 

 style. D, flower of Lobelia. The tubular corolla is opened at one side, per- 

 mitting the style and encircling stamens, g, to protrude. E, section of flower, 

 showing the anthers, a, united about the style and stigma. F, relation of 

 stigma to anthers. At right the section shows the anthers cohering about the 

 bushy style, which acts later as a brush sweeping out the spores. At the left 

 the style has grown beyond the anthers and the stigmatic lobes are spreading 

 apart. 



