LYELL ON THE EOCENE BEDS OF NORTH AMERICA. 429 



Lunulites is also considered to be identical with the species found 

 in Virginia. The Polyparia of the crag exhibit, therefore, a 

 marked absence of the genera characteristic of high temperatures. 

 The Touraine miocene strata contain, according to the fine series 

 collected by Mr. Lyell, about nine species of Anthozoa and three 

 of Lunulites, the former including an Anthophylluni, believed to 

 be the species found in Virginia, two Turbinolice and two Astrece, 

 the whole indicating a somewhat greater temperature than that of 

 the crag. The Bordeaux and Dax deposits include, according to 

 M. Michelin's work on the fossil corals of France, eleven lamelli- 

 ferous Anthozoa and two Lunulites, the former comprising a 

 Dendrophyllia, believed to be identical with a Touraine species ; 

 six Astrece, one Gemmipora, one Porites, and two Madrepores, or 

 an aggregate representative of a Red Sea list of polyparia. Lastly, 

 the Turin polypidoms, for a knowledge of which I am wholly in- 

 debted to M. Michelin's work, present no less than 73 species of 

 laraelliferous Anthozoa, a tabulated list of which will bear a 

 detailed comparison, as respects genera, with similar summaries of 

 Red Sea, or tropical polypidoms. From these data it may perhaps 

 be inferred, that the American deposit was accumulated in a 

 climate superior to that of the crag, possibly equal to that of the 

 faluns of Touraine, but inferior to that of Bordeaux." 



2. Observations on the White Limestone and other Eocene or 

 Older Tertiary Formations of Virginia, South Carolina, and 

 Georgia. By Charles Lyell, Esq., M.A., F.R.S., &c. 



The tertiary deposits occupying a lower position than the 

 Miocene strata described in the last paper, were first referred by 

 Mr. Conrad to the Eocene period, in the " Journal of the Academy 

 of Natural Sciences" for 1830. Some of these strata have been 

 observed by Mr. Conrad on the Potomac at Fort Washington in 

 Maryland (" Fossil Tertiary Shells," p. 30.) ; but the most northern 

 which I myself examined were in Virginia, at Richmond, at 

 Petersburg, and at several points on the James River. The for- 

 mation in this region consists in great part of greensand and 

 marl, containing green earth, so precisely like that which charac- 

 terises the cretaceous strata of New Jersey, that were it not for 

 the distinctness of the fossil shells, it would be impossible in many 

 places to separate these deposits by mere reference to their mineral 

 composition. 



Farther south, in N. and S. Carolina, and in Georgia, the 

 eocene formation acquires a larger development and a new mineral 

 type, consisting of highly calcareous white marl and white lime- 

 stone, and passing upwards, especially in Georgia, into red and 

 white clays, ferruginous sands, with associated layers of burrstone 

 and siliceous rock. This calcareous form of the eocene rocks on 

 the Santee River and elsewhere, had led some geologists to con- 

 sider the solid limestones as an upper secondary or newer cre- 



vol. i. G G 



