CINCHONA TREES. 235 



In this brief sketch of a great subject, there are oj 

 necessity a vast number of important products of the 

 equatorial zone, which we have been obliged to pass 

 over unnoticed. Some of these are valuable as sup- 

 plying various kinds of nutritious foods. In this cate- 

 gory, we need only enumerate the beautiful cacao tree 

 (Theobroma Cacao] from which cocoa, and its various 

 preparations, such as chocolate, are obtained. 



Then there are the sago palms, of which there are 

 several species yielding this useful commodity. Also 

 the different kinds of cassava, which produce tapioca : 

 and arrowroot, prepared from the root of the Ma- 

 ranta Arundinacea, and we believe, from other var- 

 ieties of this species of plants; also in Queensland, it is 

 largely produced from the Canna Edulis. 



There are, moreover, quite a long list of trees and 

 plants yielding various important commercial products 

 of the torrid zone : as producers of many kinds of 

 timber and cabinet woods; valuable oils, gums, and 

 spices ; tanning barks, dye stuffs, etc., etc. and last 

 but not least, medicinal plants and drugs. We feel 

 that this section would be chargeable with a grave 

 omission, if we were to close it without a notice of a 

 single example of the latter, which out of the medi- 

 cinal treasures of these great forests, has conferred 

 priceless benefits upon humanity: we refer to the 

 well-known medicine quinine, an alkaloid extracted, as 

 we are all aware, from the bark of the Cinchona 

 tree; according to Bentham and Hooker, thirty-six 

 species of this tree have been discovered, but not 

 more than a dozen of them have been utilized. * All 



* Encycl. Brit., Vol. v, p. 781. 



