PREFACE VII 



the geaera belonging to several other natural orders, will also be found 

 in company. In short, upwards of SCO plants out of 1073, enumerated 

 ia this Flora, will be found congregated together, by a slight modifica- 

 tion of the Sexual System, almost as completely as under the Natural 

 method. Having them thus grouped, their affinities and true charar. 

 tor may be studied as thoroughl}', and nearly with the same conveni- 

 ence, as under any natural arrangement. 



It will be observed, that I have throughout referred to, or used as a 

 text-book, Dr. Beck's excellent work on the Botany of the Northern 

 and Middle States, — citing it for all the species which are here given 

 by the same names: But, inciting Dr. B. (or any other Author) for 

 a species, it must not be supposed that I have quoted him verbatim. 

 I have used, without hesitation, the language and descriptive phrases of 

 others, where they appeared most appropriate ; but have taken the lib- 

 crty to modify, or add to, such descriptions, whenever my own obser- 

 vations seemed to warrant it. The only innovation in which I have 

 indulged, in the use of descriptive terms, is in the employment of the 

 words ovate, and ovoid, to convey distinct ideas. — as explained in the 

 Glossary: — a distinction which appears to me to be both convenient 

 and practically useful. 



Instead of placing th9 Cultivated Plants in an Appendix, as was 

 done in my Catalogue, I have thought it best to insert them in their 

 proper places throughout the work; but, in order to enable the reader 

 to distinguish them at a glance, I have had the descriptions printed in 

 italic^ — and have thus rendered the cultivated species, in some sort, as 

 distinct from the others, in -tl*e book, a* they are in our fields and gar- 

 dens. 



I was unfortunate in not receiving some works, which I wished to 

 consult, until it was too late to profit by their contents. This was par- 

 ticularly the case with Kuntii's Agrostographia, and the 5th Part 

 of Db Cahdollb's Prodromds. The want of the latter I especially 

 regret, — as I think the distinguished Professor of Geneva has materially 

 improved upon the labors of Lxssiko, among the Syngenesious 

 plants. 



Prefixed to this volume is a small >iap of the County, intended as 

 a guide to some of the most interesting localities, — as well as to in- 

 dicate their relative positions; and, with the further object of promot- 

 ing the study of the Vegetation in connection with the character of the 

 Rocks beneath, I have had the map colored geologically, in conformity 

 with the views of Prof. IIevut D. Rogers, the Geologist now in the 

 service of this State, — who politely designated the geological features, 

 and the order of coloring, here exhibited. It is proper to observe, 

 however, that the range of hills, on the South side of the great Lime- 

 stone Valley, usually called J\tica-sl<i!e in the text, is designated as 

 Talc-slate, by the coloring on the map. 



West-Chester, Pa. 



April, 18J7. 



53" The reader will please to correct a palpable typographical error, in ihe 

 second line of the paragraph at the foot of pa^eGM— where Instead of " 260 NAW- 

 sal Orders,' 9 it should read 2(x> Natural Orders. 



