178 PROCEEDINGS OF 



1 have here given a view of all the strata known above the white limestone which 

 prevails so extensively in Southern Alabama and Georgia, and which is evidently a 

 link in the widely distributed cretaceous series. The lower tertiary in the Southern 

 States is generally in limited basins or depressions in this limestone. Although at 

 Claiborne the actual junction or relative position of the two formations is not ex- 

 hibited, yet the latter rock can be traced, as well as identified by its fossils, from a 

 spot six miles west of Claiborne to St. Stephens on the Tombeckbee river, where it 

 is seen to underlie the lower tertiary strata, a short distance north of the village. 

 The following section, though constructed from recollection after a lapse of seven 

 years, will convey an idea of the cliff at St. Stephens, 



St. Stephens. 



River Level. 



A. Newer cretaceous limestone. 



B. Alluvium. 



C. Eocene. 



I have already indicated those fossils which are common to both formations, but 

 it is not unlikely than another of great importance will yet be added to the number. 

 This is the Zcuglodon, or the gigantic Basilosaurus, found on the Washita river, 

 in Louisiana, completely enveloped in eocene fossilliferous •' marl." It is yet, 

 however, uncertain whether this envelope may not have fallen from the cliff above 

 upon the exposed remains, though their tertiary origin is more probable. In the 

 limestone, specimens of the jaws and teeth, and many vertebrae have been discovered. 

 I received some years since, from Alabama, some of these remains, and the vertebrie 

 were reported to have laid upon the ground when first discovered, in so regular a 

 line, as to suggest the idea of their having been undisturbed from the time of the 

 animal's death. Judging from the extent of this line of vertebrae, the Zeuglodon 

 was supposed to have been one hundred and fifty feet in length, which is doubtless 

 a great exaggeration. Portions of nine individuals, it is said, have been found in 

 Alabama. 



The following fossils, most of them described by Dr. Morton, constitute the group 

 by which this formation is recognised : Nummulitea Mantelli, Pecten perplanus, P. 

 Ponhoni, Plagiostoma diimosum, Ostrea panda, O. cretacea, Modiola creiacra, Oy- 

 phaa vomer. Nautilus alabamensis, Scutella Rogersi. 



The rock is finely developed, and the fossils very numerous, between Claiborne 

 and St. Stephen's, in Alabama, particularly at the latter locality, where myriads of 

 the Nummulites Mantelli, (Morton,) cover tlie surface of the decomposing rock. 



Geographical range of Lower Tertiary. — ^Tho most northern locality I have seen 

 IS near Long Branch, in New-Jersey, where the fossils, though generally casts in marl, 

 with a chalky coating, are very readily identified with the Claiborne species. The 

 localities in Maryland have already been indicated. In Virginia, the formation 

 occurs on the Rappahannock, below Fredericksburg, on the Pamunkey river, and 



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