EXOGENOUS OU DICOTYLEDONOUS PLANTS. 



433 



The febrifugal properties of the former depend on the presence of 

 two alkaloids, Cinchonia and Quinia, both combined with Kinic acid. 

 The Quinquina barks, which are derived from some species of Ex- 

 ostemma and other West Indian, Mexican, and Brazilian genera, 

 contain neither cinchonia nor .quinia. The bark of Pinckneya pu- 

 bens, of the Southern United State?, has been substituted for Cin- 

 chona. — The true Ipecacuanha is furnished by the roots of Cepha- 

 aelis Ipecacuanha of Brazil and New Granada. Its emetic principle 

 (called Emetine) also exists in Psychotria emetica of New Granada, 

 which furnishes the striated, black, or Peruvian Ipecacuanha. The 

 order likewise furnishes Coffee, the horny seed (albumen) of Coffoea 

 Arabica. According to Blume, the leaves of the Coffee-plant are 

 used as a substitute for tea in Java. — To this order maybe ap- 

 pended, either as a suborder, or, as in a general work it is more con- 

 veniently regarded, the 



841. Ol'd. Logailiacesc, which may be briefly said to be Rubiacere 

 with a free calyx, and manifestly connected with the Cinchoneaj 

 through the Iloustonia section of Oldenlandia, with a partly free 



FIG 872. Oldenlandia (Iloustonia) carulea. 873, 874 The two sorts of flowers that differ- 

 ent individuals bear, with the corolla laid open ; one with the stamens at the base, the other 

 at the summit of the tube: the lower figure shows also a section of the ovary 875. Cross- 

 section of an anther, magnified. 876 Anther less enlarged, opening longitudinally. 877- 

 Capsule with the calyx. 878 879 Views of the capsule iu dehiscence. 880. Diagram of a 

 cross section of the unexpended flower. 



37 



