433 



B. True Cinchonas with a White Epidermis. 



I. Pale Barks. 



7. White Loxa Bark, Cinchona sp.? 



II. Yellow Barks. 



8. Hard Carthagena Bark,... Cinchona cordifolia, Mutis. 



9. Fibrous Carthagena Bark,. Perhaps C. cordifolia. 

 10 Cuzco Bark, Cinchona sp.? 



11. Orange Bark of Santa-Fe,.C. lancifolia, Mutis (C. angustifolia, P.) 



III. Eed Barks. 



12. Red Bark of Santa-Fe', C.oblongifolia,lfais(C.magnifolia.R.andP.) 



Cinchona bark contains two alkaloids, Cinchonia and Quina, to which 

 its active properties are due ; the former is best obtained from Gray 

 bark, the latter from Yellow bark. In combination with these, there 

 exists an acid called Cinchonic or Kinic acid. Cinchona bark is used 

 medicinally as a tonic and antiperiodic, in cases of dyspepsia, neuralgia, 

 and intermittent fever. It has been administered in the form of in- 

 fusion and tincture ; but, at present, the disulphate of Quina is the 

 chief preparation used. The genus Exostemma yields various kinds of 

 false Cinchona bark, which do not contain the Cinchona alkalis. In 

 this genus the stamens are exserted, whereas in Cinchona they are 

 included. The following are some of the false barks noticed by Pereira: 



1 St. Lucie or Piton Bark, Exostemma floribundum. 



2 Jamaica Bark, E. caribfeum. 



3 Pitaya Bark, Exostemma sp.? 



4 False Peruvian Bark E. peruvianum. 



5 Brazilian Bark, E. souzianum. 



Pinckneya pubens yields the fever-bark of Carolina. 



904. Some of the plants of this order have emetic and purgative 

 qualities. Cephdelis Ipecacuanha yields the Ipecacuanha of the Pharma- 

 copoeia. The plant is found in the woods of several Brazilian provinces, 

 as Pernambuco, Bahia, and Rio Janeiro. The roots, which are the offi- 

 cinal part, are contorted, knotty, and annulated, and about the thickness 

 of a goose-quill. They are used as emetic and diaphoretic remedies, in 

 the form of powder or wine. Their active ingredient is an alkaloid 

 called Emeta or Emetine. Besides this brown or gray annulated 

 Ipecacuanha, there are spurious kinds, such as striated or Black Peru- 

 vian Ipecacuanha, the produce of Psychotria emetica, and white or amy- 

 laceous Ipecacuanha, furnished by Richardsonia scabra (brasiliensis,) a 

 native of the provinces of Eio Janeiro and Minas Geraes. Some of 

 the species of Psychotria, Cephdelis, and Randia, are said to act so 

 violently as to produce poisonous effects. 



905. Among the astringent plants of the order, may be noticed 

 Uncaria Gambir, which supplies a kind of Catechu, known by the 

 name of Gambeer. Of the plants furnishino; articles of diet, the most 



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