Geological Society. 507 



red sandstone of Blossburgh in Pennsylvania, proved to be the repre- 

 sentative of the old red sandstone or Devonian system of Great Bri- 

 tain, in consequence of its inclosing remains of Holoptychius and 

 Coccosteus. This deposit is succeeded in descending order by others, 

 referable, on account of their testaceous remains, to the lower part of 

 the same system, and these are again underlaid by limestones and 

 shales, especially at Lockport and Rochester, charged with Ptilo- 

 dictya lanceolata and other Silurian corals and fossils. The lowest 

 deposit alluded to by Mr. Hall is the Medina sandstone. The fol- 

 lowing sectional list, in descending order, is copied from his com- 

 munication : — 



Red sandstone. 



Sandstone and shale, abundance of fossil shells. 



Shale, with thin layers of sandstone ; Fucoides, abundance ; few 



shells. 

 Green and black shale, several hundred feet thick. 

 Black shale. 

 Moscow shale. 

 Encrinal limestone. 

 Ludlowville shale. 

 Thin mass, with Bellerophons. 

 Shale. 



Thin limestone, with fossils. 

 Marcellus shale. 

 Limestone, with hornstone. 

 Onondaga limestone. 



Onondaga saliferous group, containing gypsum and salt-springs. 

 Lockport limestone. 

 Rochester shale. 

 Limestone. 



Green shale, with fossils. 

 Pentamerus limestone. 

 Green shale and iron ore. 

 Red and grey sandstone, Medina sandstone*. 

 With respect to the Onondaga saliferous group, Mr. Murchison 

 points out its extremely low geological position, resting upon a cal- 

 careous stratum, which has been proved by its organic remains to be 

 the equivalent of the Wenlock limestone ; and he states that it is 

 of higher antiquity than the oldest salt-bearing beds of Russia. Mr. 

 Murchison also alludes to the great value of Mr. Hall's communica- 

 tion in proving the wide application of the palaeozoic succession esta- 

 blished in Great Britain. 



June 2. — " On the Faluns of the Loire, and a comparison of their 

 Fossils with those of the newer Tertiary Strata in the Cotentin, 

 and on the relative age of the Faluns and Crag of Suffolk, " by 

 Charles Lyell, Esq., V.P.G.S. 



In a paper " On the Crag of Norfolk and Suffolk," read in 1839f, 



* For detailed accounts of the New York Devonian and Silurian Systems 

 and their Organic Remains, see the Geological Reports of the State for 

 1838, 1839, 1840. 



t Proceedings, vol. in. p. 171- 1839. 



