CHAPTER X 

 CAFFEINE-YIELDING PLANTS OF THE WORLD 



Economic Plants Possessing the Alkaloid Caffeine: 

 CsHioN.O^ 



SPECIES FAMILY PART APPROXIMATE % 



Coffea species Rubiaceae Seed 0.5 to 2.2% 



Leaf 1.3% 



Geographical Distribution : — Africa. Now introduced through- 

 out the tropics and subtropics of the world. 



The caffeine-content varies greatly within the genus. For infor- 

 mation regarding the various species of coffee^ see the section devoted 

 to the species in question. For extremes as regards the caffeine-con- 

 tent, see: 



Coffea arah'ica L. var. Humhlotiana (Baill.) Froehner. 



Coffea arah'ica L. var. amarella Hort. ex Froehner. 



Coussarea hydrangeaefolia Benth. & Hook. Rubiaceae Leaf used 



— ? % 



Geographical Distribution: — Bolivia (Santa Cruz and Bellavista 

 regions). 



Thea sinensis L. Theaceae Leaf i to 4.8% 



(average 2 to 2.5%) 

 This species is the chief source of tea. 

 Geographical Distribution : — China. 



Thea assamica Mart. Theaceae Leaf i to 4.8% 



(average 2 to 2.5%) 

 Geographical Distribution: — Upper Assam; Province of Cachar. 

 For cultivated areas by introduction, see map. 



Cola acuminata (Beauv.) Schott & Endl. Sterculiaceae 



Seed 2.3 to 3.6% 



Synonymy: — Cola vera K. Schum. Sterculia acuminata Beauv. 



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