DEVELOPMENT OF PLANTS 



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associated with the twisting of the petals in the bud and the 

 opposite arrangement of the leaves as distinguishing features 

 of the order (Fig. 328, B-D). Note should be made of the fact 

 that the two pistils often do not cohere, doubtless a survival of 

 a more primitive condition. The Gentianales include the ash 



Fig. 328. Primulales and Gentianales: A, flower of loosestrife {Steiro- 

 nema). Above flower in section, showing cohesion of single row of stamens 

 to base of corolla and the numerous ovules on a free central placenta. These 

 are the most important characteristics of the order. B, fringed gentian 

 {Gentiana), showing leaf arrangement and twisting of petals in bud, b, char- 

 acteristics of the order. C, section of flower. D, fruit, the two carpels 

 separated. 



{Fraxinus) , lilac (Syringa), Forsythia, olive (Olea), valued for fruit 

 and oil, fringe tree {Chionanlhus) , privet (Ligustrum), jasmine, 

 Strychnos, yielding the alkaloid strychnine, oleander (Nerium), 

 the gentians, marsh pink (Sabbatia), the aquatic floating heart 



