PREFACE. 



This handbook presents short descriptions of the seed-plants growing 

 naturally in Lancaster County, Pennsylvania, together with statements of 

 the habitats and distribution of the species, and also their flowering sea- 

 sons. Analytical keys, formed by contrasting diagnostic characters, pre- 

 cede the descriptions of the families, genera, and species, and a general key 

 to the orders precedes the descriptive flora. 



The region covered by this flora has been the scene of almost continuous 

 botanical exploration and study for nearly a century and a half, definitely 

 beginning with the observations of Gotthilf Heinrich Ernst Muhlenberg at 

 Lancaster in the year 1780. However, only one authentic list 1 of the 

 flowering plants known to grow naturally in the county has been published. 

 In the preface to this catalogue the author says : 



" The following catalogue is based upon the results of explorations 

 made during a residence in the city of Lancaster between the years 1853 

 and 1866. All the plants contained in it were seen and examined by the 

 author, with the single exception of Quercus phellos, L., 2 and specimens of 

 the rarer species, about which there might be any question, are at hand for 

 reference in his own herbarium 3 and in the herbaria of the Linnaean 

 Society 4 and the State Normal School at Millersville." 



" In the annals of American Botany, Lancaster county is classic 

 ground. It was the home of the distinguished Muhlenberg, who probably 

 collected on her soil, at the beginning of the century, many of the species 

 first described by him and by the German botanist Willdenow, with whom 

 he carried on a long and active correspondence. He left behind him in 

 manuscript a Flora Lancastriensis, which unfortunately has either been 

 lost, or is no longer accessible." 5 



" The aim of the author has been to lay a good foundation upon which 

 any one who may wish to continue the work hereafter can build with con- 

 fidence, for the field is by no means exhausted. . . ." 



1 An enumeration of the indigenous and naturalized plants found growing 

 in the County of Lancaster, Pennsylvania, by Thos. C. Porter, published in 

 An Authentic History of Lancaster County, by J. I. Mombert, 1869. 



2 This species is not uncommon on the Martic Hills along the Pequea Creek, 

 s Now at Lafayette College, Easton, Pa. 



* Linnaean Society of Lancaster. 



s The manuscript of Muhlenberg 's Flora Lancastriensis, and seven other 

 manuscripts relating to the plants of Lancaster County, have since been found 

 in the library of the American Philosophical Society at Philadelphia, Pa. 



