6 PREFACE. 



formidable undertaking. The plan and nature of this publication 

 are obviously such as to preclude all expectation of emolument. 

 It is our determination, however, to carry on the work to its com- 

 pletion (in about ten volumes like the present), if the patronage re- 

 ceived shall warrant the hope of a moderate remuneration to the 

 artist. The ample and rapidly accumulating materials at my dis- 

 posal, both of specimens in the Herbarium, and of living North 

 American plants in the Botanic Garden under my charge, and the 

 prompt assistance offered by a large number of zealous correspond- 

 ents, while they afford unusual advantages for the purpose, render 

 me increasingly desirous to turn them to useful account by prosecut- 

 ing an undertaking which may serve to facilitate the more thorough 

 study of Botany in this country, and perhaps contribute in some de- 

 gree to the general advancement of the science. 



The higher character of the later as compared with the earlier 

 executed analyses, as well as the further improvement which will be 

 manifest to the experienced botanist in the second volume, — now in 

 an advanced state of preparation, — is attributable to the increasing 

 botanical knowledge of the self-taught artist who is associated with 

 me in the work. And, although I am alone responsible for the text, 

 I must in justice add, that whatever of original value these illustra- 

 tions may be found to possess is largely owing to the scientific in- 

 sight and the careful investigations of Mr. Sprague, as well as to 

 his skill and accuracy in delineation. • 



The plates are engraved upon stone, in a style (capable of further 

 improvement) well adapted to this class of subjects, by*Mr. Joseph 

 Prestelc, a worthy artist, formerly of Munich, but now and for sev- 

 eral years past resident at Ebenczer, near Buffalo, New York. 



As to geographical extent, this work is intended to comprise all the 

 genera which have indigenous representatives within the States of 

 the Federal Union as now constituted. It therefore includes Texas, 

 but not the country west of the organized States of Arkansas and 

 Missouri. 



ASA GRAY. 



i Iambridge, April 20, 181 s . 



