DEVELOPMENT OF PLANTS 



405 



and interesting order includes a great variety of our common 

 plants, herbs and trees, as the white and yellow water lilies 

 {Nymphaea and Castalia), buttercups (Ranunculus), marsh 



Fig. 304. Advanced type of the Chenopodiales : A, shoot of Mclandry- 

 num bearing flower with perianth differntiated into calyx, ca, and corolla, 

 c. B, section of flower, showing the relation of calyx to corolla and 

 the concealment of the nectar glands at the base of the ovary. Access to 

 the corolla tube is guarded by an outgrowth on the petals, as shown in C, 

 which, assisted by the styles or stamens, so effectually closes the mouth of 

 the tube that only insects with long tongues can reach the honey. 



marigold (Caltha), windflower (Anemone), Hepatica, rue 

 (Thalictrum) , columbine (Aquilegia), larkspur (Delphinium), 

 monkshood (Aconitum), may apple (Podophyllum), magno- 

 lia, tulip tree (Liriodendron) , Sassafras, spice bush (Benzoin), 

 etc. In this order we have again reached the point, just as in 

 the monocotyledons (see Liliales), where the flowers are more 

 usually solitary and conspicuous, owing to the development of 

 large, showy perianths that are more frequently differentiated 

 into calyx and corolla. The flowers, however, are very simple, 

 as is indicated by the regular and hypogynous arrangement of 

 the parts (Fig. 305). The receptacle is frequently elongated 



