4 THE POTOMAC OK YOUXGER MESOZOIG FLOKA. 



Prof. William B. Rogers, in his annual reports on the geology of Vir- 

 ginia,^ made more than forty years ago, mentions the finding of certain 

 plant-fossils in the vicinity of Fredericksburg. He does not describe any 

 of them, but considers thera as indicating for tlie Mesozoic strata at that 

 town an age not far from that of the Purbeck of England. 



Mr. R. C. Taylor" gives an account of "certain fossil dicotyledonous 

 plants in the secondary strata of Fredericksburg." He speaks briefly of 

 some of the features of the Potomac formation in the vicinity of that town, 

 and mentions rather vaguely the location of the plants. He says that at 

 his request some of the impressions were furnished to the geological society 

 by Mr. F. Shepherd. These seem to have been few in number and poorly 

 preserved. Mr. Taylor gives in his article some figures and imperfect de- 

 scriptions of these fossils. The delineations are so vague that little can be 

 learned from an inspection of them. No dicotyledons are indicated. Cer- 

 tain long stems of succulent plants are mentioned as appearing in the form 

 of hollow casts. These may be the Frcnelopsis ramosissima, so abundant at 

 Fredericksburg. Some coniferous twigs with acicular leaves and some 

 ferns are figured, but they can not be specifically determined. His figure 3 

 is without doubt a Sdero]}teris, difi"erent from the one (^S. elliptka) found by 

 me, being a smaller form. I have seen none of the plants mentioned by 

 Professor Rogers and none of those described by Mr. Taylor, and, notwith- 

 standing pei-sistent search, I have failed to find the locality mentioned by 

 the latter gentleman. It^^^eems, from what he says, to be diff"erent from the 

 one which yielded me so many fossils. 



The mention by Professor Rogers of the discovery of plant-fossils in 

 the Fredericksburg beds and the account given by Mr. Taylor seem to 

 have attracted very little attention. 



Mr. F. B. Meek many years ago made a search for fossils in the clays 

 lying on the line of the Baltimore and Ohio Railroad between Washington 

 and Baltimore. He succeeded in finding at Baltimore a few well-preserved 

 impressions, which are mostly those of ferns. These were subsequently 

 placed in the collections of Columbia College, New York, where they now 

 are. Dr. J. S. Newberry kindly loaned them to me for description. An 



'A reprint of Anuual Reports on the Geology of the Virginias, 1884, pp. 7, 71-2. 

 i^ Trans. Geol. Soc. Pennsylvania, vol. 1, 1835, pp. 314-325, PI. XVIII, XIX. 



