



ADVERTISEMENT. 



WHEN this revised Edition was commenced, it was contemplated 

 with the aid of kind Friends to insert a brief description of all 

 the indigenous species of the Vegetable Kingdom which had been 

 detected in our County, together with such introduced plants as 

 had become naturalized, or were CULTIVATED for useful purposes. 

 It soon became apparent, however, that the lower Orders (especially 

 the Fungi) were so multitudinous, as well as obscure, that it would 

 require more time to accomplish the undertaking, than /, at least, 

 had any right to reckon upon. It was found, also, that to include 

 the whole, would render the work inconveniently voluminous. A 

 descriptive enumeration of the Fungi, alone, would make a respect- 

 able volume. It was therefore concluded to omit all below the 

 Lichens, and leave that portion of our Botany to the future enter- 

 prise of our Chester County Naturalists. 



For the account of our Mosses and Hepaticae, I am indebted to 

 the researches, and kind attention, of THOMAS P. JAMES, Esq. an 

 enthusiastic Bryologist of Philadelphia. The Lichens have been 

 collected and determined by Dr. EZRA MICHENER, of this County, 

 a Naturalist from whose acumen, diligence, and indomitable per- 

 severance, we may fairly expect as thorough an exploration of every 

 department of our Cryptogamy, as the active duties of his Profes- 

 sion, and the life-time of an Individual, will permit. I am gratified, 

 moreover, in knowing that a few zealous and faithful Lovers of 

 Nature are engaged with him, as Collaborators, in the laudable 

 attempt to prepare a comprehensive Natural History of the County 

 of Chester. w. D. 



