430 



EXOGENOUS OR DICOTYLEDONOUS PLANTS. 



thus (Button-bush), Hedyotis, and an immense number of tropical 

 genera. Their stipules distinguish them from Caprifoliacea?. 



807. Subord, Logauieffi, or SpigeliefB, have opposite stipulate leaves, 

 and the ovary nearly or entirely free from the persistent calyx. 

 Ex. Mitreola, Spigelia (the Pink-root), and other genera interme- 

 diate between Rubiacea? and Apocynacea3. 



808. Very active, and generally febrifugal properties prevail in 

 this large order. The roots of Madder yield a most important 

 dye: and many Galiums have a similar red coloring matter. 



The division Cinchonese furnishes two of the most valuable known 

 remedial agents, namely, Peruvian lark, or Cinchona, and Ipecac- 

 uanha. The febrifugal properties of the former depend on the 

 presence of two alkalis, Cinchonia and Quinia, both combined 

 with Kinic acid. The Quinquina larks, which are derived from 

 some species of Exostemma and other West Indian, Mexican, and 

 Brazilian genera, contain neither cinchonia nor quinia. The bark 

 of Pinckneya pubens, of the Southern United States, has been sub- 

 stituted for Cinchona. The true Ipecacuanha is furnished by the 

 roots of Cephaselis Ipecacuanha of Brazil and the mountains of 



FIG. 746. Piece of Rubia tinctoria (the Madder) in flower. 747. The fruit. 748. The two 

 constituent portions of the fruit separating. 749. Vertical section of one carpel, showing the 

 curved embryo. 750. Section of a flower of Galium. 



FIG. 751. Cephalanthus occidentalis, the Button-bush. 752. A flower, taken from the head. 

 753. The corolla laid open. 



