DESCRlPTIOlsr OF SPECIES. PP. 67 



fied by somepalseo-bolanists as P.iilumosa, from the Lower 

 Coal Measures of America. This form might be distin- 

 guished by the varietal name parva. 



We find a great number of well preserved forms of tlie 

 true dentata, at Cassville, among which we find most of the 

 forms figured by Brongniart, Geinitz and Heer; but we have 

 as yet seen it at no other locality. 



Pecopieris pteroides, Brongt. 



This is one of the most widely distributed plants that we 

 find in the Upper Carboniferous Strata, it being found at 

 every locality where we have examined the flora of the 

 Waynesburg Coal. Near Arnettsville, between Fairmont 

 and Morgantown, in Monongalia Co., it is very abundant in 

 the roof shales of this coal seam, and compound or primary 

 pinnae were seen 1^- feet long and a foot wide. Our plant 

 has the facies and nervation of Grermar's, given on plate 

 XXXVI, in his Yerst. d. Stein. Form. v. Wettin u. Lobj. 

 At Carmichaels, Penn. it is very abundant. 



Pecopteris Pluckeneti, Brongt. PI. XXI, Figs. 4 and 5. 



At West Union, in Doddridge Co. we find countless num- 

 bers of this plant, with every known and some new forms. 

 Indeed the variableness of the plant is simply astonishing, 

 and can be appreciated only when we have, as here, a great 

 amount of well preserved material, which enables us to 

 follow it through its many changes. Besides being thus 

 abundant at this locality it is a widely diffused plant, for 

 we find it at numerous other localities, in the Waynesburg 

 Coal, as well as at all the higher horizons nearly to the to}) 

 of the series. Figs. 4 and 5 give the most common forms 

 of the plant as found at West Union, and it will be seen 

 that though they do not differ essentially from some of the 

 numerous types already figured by others, yet have a facies 

 of their own. This plant must have been an arborescent 

 species, from the great size which some of the specimens 

 show. Some of the stipes are 5 or 6 inches in diameter. 

 and fragments of fronds were seen 18 to 24 inches in length 

 and width. The plant becomes much rarer as we ascend 



