PALEONTOLOGIC NOTES FLOEA 177 



transition to that of the Buck Mountain and partaking in some respects 

 of features characterizing the Allegheny flora. 



In correlating these floras with those from other portions of the Ap« 

 palachian basin, Mr White recognizes in the lower part of the Lower 

 Lykens division forms wholly characteristic of the Pocahontas coal in 

 the Virginias and occurring there, as in the Southern Anthracite fleld, 

 with very narrow vertical distribution. The iipper portion of this 

 Lower Lykens division is closely related to the Quinnimont or middle 

 portion of the New River section, and the correlation is clear for that as 

 for its equivalent in Kentucky, Tennessee, and Alabama. The Upper 

 Lykens flora is even more sharply characteristic. The elements of the 

 flora in the roof of Lykens 3 are so preponderatingly identical with those 

 in the roof of the Sewell coal bed in West Virginia and of the Sewanee 

 in Tennessee that Mr White regards those coal beds as practically con- 

 temporaneous. As has been stated already, the stratigraphic study con- 

 flrmed Mr White's correlation of the Sewell and Sewanee horizons ; those 

 localities are separated by an interval as great as that between the Sewell 

 and Lykens Valley localities. The highest flora, 245 and 210 feet below 

 the Buck Mountain, that of Lykens coal 1, is nearly allied to the flora 

 of the Mercer coal beds and possibly contemporaneous with a flora in the 

 Gladesville sandstone of southwest Virginia, as well as in Breathitt 

 county of Kentucky, which accords closely with stratigraphic determina- 

 tions in Stevenson's surnxnary, made several years afterwards.* This 

 upper portion, ending at 210 feet below the Buck Mountain, appears to 

 be equivalent to the lower part of the Kanawha formation. The Camp- 

 bell's Ledge flora, in the northern Anthracite field, only a few feet above 

 the Shenango shale, or highest beds of the Mississippian, seems to be 

 related to that of this upper or transition series, its place being near the 

 Mercer horizon, a little way higher than given in Stevenson's Pottsville 

 correlation, where it was placed at the horizon of the Sharon coal bed. 



The relations of the Buck Mountain flora are considered in this paper. 

 In all other publications referring to the Anthracite fields the Buck 

 Mountain coal bed has been taken as the bottom of the Allegheny. This 

 boundary, fixed ai'bitrarily by Professor H. D. Rogers, is convenient, 

 as that coal bed is persistent and important in by far the greater part 

 of the Southern and Middle fields. But Mr Wliite has shown conclusively 



* In a later paper, "Deposition of the Appalachian Pottsville," Mr White is in- 

 clined to see the Sharon coal horizon above the Gladesville sandstone, which would 

 carry the upper limit of the Pottsville above the plane assigned by Stevenson. It is 

 wholly probable that the stratigraphic evidence will confirm this conclusion, for the 

 measurements on which Stevenson based his correlation of the Gladesville sandstone 

 with the sandstone of Kentucky have been proved defective. 



