PREFACE. 



titioners, most valuable remedial agents. A medical man 

 should also be aware of their existence, as he may at any 

 time be called upon to counteract their effects. 



In arranging his materials the author has generally 

 noticed at greatest length those plants which he supposes 

 to be most important ; while others are either very shortly 

 described, or only mentioned by name. It will be found, 

 that the technical descriptions have been carefully framed 

 in accordance with the existing state of Botanical know- 

 ledge, and according to the most approved rules of modern 

 science. The student will therefore be able to use them 

 as models upon which to familiarise himself with the art 

 of descriptive Botany. Nevertheless, it has not been 

 thought necessary to provide in all cases original descrip- 

 tions ; and consequently although a great many are so, 

 many others are only amended, altered, or corrected from 

 the works of other Botanists. In such a collection of facts 

 as this is much originality can hardly be expected ; it will 

 however be found, upon reference to the articles Cin- 

 chona, Croton, Rheum, Convolvulus, and others, that 

 original investigation has not been neglected when it 

 seemed to be required. 



It will be generally found that the authorities for the 

 medicinal properties ascribed to species are those of the 

 writers whose works are quoted among the Botanical re- 

 ferences; if it is not so the exact authority for a statement 

 is usually expressly mentioned. 



For the convenience of those who may wish to use this 

 work as a catalogue of the contents of the Medicinal de- 

 partment of a Botanic Garden, all the species are numbered 

 consecutively ; and it is intended that the same numbers 

 should be preserved, in case the work should ever reach a 

 second edition ; all additions being introduced with letters 

 after the numbers next to which they may be placed. 

 This intimation i» given for the satisfaction of those who 

 may be desirous of combining the advantage of a catalogue 

 with the information the work contains. 



In the present state of systematical Botany no two 



