1894.] " [Lyman. 



1890-91). Their description of the rock-beds shows a good deal of resem- 

 blance to those of Newark. Fletcher, in his last report, gives several 

 detailed sections of Permian rocks up to five thousand and eight tliousand 

 feet in thickness. It seems hardly probable that no traces of so vast a 

 formation should be found in the eastern United States near either the 

 Mesozoic or Paleozoic rocks with which it is so intimately associated in 

 Nova Scotia and Prince Edward Island. 



It would seem, then, that the Mesozoic age of the beds of Newark is 

 not so thoroughly certain but that it might be worth while for paleontolo- 

 gists to ree.Kamine with renewed care the indications of the fossils that 

 really bear on the point. For undoubtedly the very scanty and imperfect 

 testimony of the fossils already known ; the apparent bias, on the one 

 liand, in favor of comparing them only with Mesozoic forms that are ex- 

 tremely remote at best ; on the other hand, the less biased partial identi- 

 fication of some Newark fossils with Paleozoic ones under conditions at 

 least equally favorable as regards skill and material ; the great thickness 

 of measures below the comparatively well-identified Rhaetic or Triassic 

 horizon of tlie Gwynedd and Phoenixville shales, the same probably as 

 the Richmond and North Carolina coal-bearing beds ; and the possibility, 

 to say the least, that some of the red beds conformably at the top of the 

 Carboniferous rocks of southwestern Pennsylvania and of West Virginia, 

 as well as some of the Permian or Carboniferous beds of eastern Canada, 

 may be of identical age with the Newark beds ; all these circumstances 

 make it seem not altogether improbable that the Newark brownstone is 

 older than the Mesozoic. 



Further on the Age of the Newark Brownstone. 



By Benjamin Smith Lyman. 



(Read before the American Philosophical Society, January 19^ IS94.) 



An additional reason for doubting the Mesozoic age of the Newark 

 brownstone may be found in the remarks of Newberry on his fossil plant 

 Dendropliycus triansiais, found at Portland, Conn., in sandstone of pos- 

 sibly the same age as the Newark brownstone. He quotes (Monograph 

 xiv, p. 82) Lesquereux's description o{ Dendrophycus Desori, found in the 

 Pennsylvania No. XI, or Umbral shales ; and adds : " I have copied this 

 description nearly entire because it is almost literally applicable to a plant 

 represented on PI. xxi of this memoir and obtained from the sandstones 

 of Portland, Conn. Wiien we consider the vast interval of time between 

 the deposition of the Umbral shale of Pennsylvania and that of the 

 Rhsetic sandstone of Connecticut, one the base of the Carboniferous sys- 



I'ROC. AMER. PHILOS. SOC. XXXIII. 144. B. I'RINTED FKB. 13, 1894. 



