EXOGENOUS OR DICOTYLEDONOUS PLANTS. 



463 



891. Ord. RafflesiaceOB : parasitic flowers, or flower-clusters (152), of 

 which the most striking is the gigantic Eafflesia Arnoldi of Sumatra 

 (Fig. 150), perhaps as much related to the last order as to any. 



892. Ord. NyctaglnacefE {Four-o'clock Family). Herbs or shrubs, 

 with opposite leaves ; distinguished by their tubular and funnel-form 

 calyx, the upper part of which resembles a corolla, and at length 

 separates from the base, Avhich latter hardens and encloses the one- 

 celled achenium-like fruit, appearing like a part of it. Stamens hy- 

 pogynous, 1 - 20. Embryo coiled around mealy albumen (Fig. G16, 

 617) ; cotyledons large. Flowers involucrate. Mirabilis (Four- 

 o'clock) has a one-flowered involucre exactly like a calyx, while the 

 real calyx resembles the corolla of a ]\Iorning- Glory. Abronia has 

 only one cotyledon to its embryo ! — Plants of warm latitudes ; many 

 occur on our Southwestern frontiers. 



1090 



1092 



1091 



loss 



1089 



893. Ord. Phytolaccacca; (Poke-weed Family). Chiefly represented 



FIG 1086, 1087. Phytolacca decandra (Pokeweed). 1088 A flower. 1089. Unripe fruit. 

 1090. Cross-section of the same, a little enlarged. 1091. Magnified seed. 1092. Section of the 

 same across the embryo. 1093. Vertical section, showing the embryo coiled around the albu- 

 men into a ring 1094. Magnified detached embryo. 



