Vi PREFACE. 



tries, authorities are cited and synonymy is given as far as they 

 relate to the American habitat, with only jjartial and general refer- 

 ences to foreign botany. 



It is intended to give with the final A'olume a full bibliogra2)hy, 

 not only of the works and articles here cited, but of all others relat- 

 imx to the North American flora. The abbreviations of titles that 

 are here used, though necessarily concise, will usually suffice for the 

 ready identification of the works cited, without the aid which such 

 bibliography would give. In some instances, however, authors of 

 single works of frequent recurrence are referred to by name only, as 

 Walter (Flora Caroliniana), Persoon (Synopsis Plantarum), Elliott 

 (Sketch of the Botany of South Carolina), Chapman (Flora of the 

 Southern States), etc. In case of several editions of the same work, 

 the first edition is the one cited unless it is otherwise specified, 

 excepting the common manuals of the Eastern flora, of which the 

 later editions have been used (Eaton & Wright, North American 

 Botany, 1841, which is the eighth edition of Amos Eaton's Manual 

 of Botany; Wood, Class-Book, 1861; Gray, Manual, 5 ed. 1869). 

 The Genera Plantarum of Bentham & Hooker has been followed in 

 the sequence of the orders, while the genera and species are arranged 

 alphabetically for greater facility of reference. The authorities 

 under each specific name, as also the citations from each author, 

 are arranged in chronological order. Citations of plates or figures 

 are made more prominent by the use of heavy-faced type ; where 

 the reference is simply to a catalogue name or habitat, without 

 any note descriptive or otherwise important, the numerals are in 

 antique type. Introduced species have the specific name in small 

 cajiitals. 



SERENO WATSOX. 



Cambridge, Marcli 1, 1878. 



