PKEFACE. 



About two years ago a number of well preserved plant 

 impressions were observed at Cassville, in Monongalia 

 County in West Virginia, in the sliale associated with the 

 coal bed worked at that village. This bed is called the 

 '* Waynesburg," in the nomenclature used in describing 

 the strata of the "Appalachian Coal Field." It is the high- 

 est worked bed which occupies any important area in this 

 great field. 



The beauty of the impressions, and the fact that some of 

 them were new, led to further examination. The result 

 was, that many new forms were found at this place ; other 

 and remote localities were visited, and it was found that at 

 many exposures the coal was accompanied by remarkably 

 fine plants. Various horizons above this bed were found 

 to afford plant impressions, many of them being new. 

 Where these horizons are exposed in the adjoining States 

 of Pennsylvania and Ohio, they appear to afford compara- 

 tively few plants. There was little prospect then, that the 

 surveys of these States would obtain material sufficient to 

 throw much light on the plant life of the upper beds of this 

 important coal field. There was also little prospect that 

 the State of West Virginia would, in any short time, author- 

 ize such a survey as would give this material to the scientific 

 world. 



As the result of our collections seemed to us to be of 



some interest and value to science, we were induced, in our 



private capacity, to study this material, and prejjare our 



conclusions for publication as a contribution to science. 



( vii pp. ) 



