the tertiary geology op the 
IK) 
Tertiary aeries, it .aay be premised at the outset that unequivocal representatives of 
both eIcuc and Miocene exist; scarcely less posit.ve ts the ex.stence of Ohgoccne 
l lits, whereas no satisfactory evidence has as yet been adduced pmv.ng he 
pr sencc; of Pliocene on our coast. The starting pent rn the correlat.ou of the 
Lenes is afforded by the well-known shell-sand layer of Cla.borne, AU who^ 
equivalency, at least in part, with the Calcaire Grossier of the Pans basm (Pans.an), 
has long been recognized. The general similarity and identity existing between the 
fossil remains of the two localities hem indicated place this determination beyond 
question. Beds representing the true “ Claibomian ’’ have been recognized m South 
Carolina, Georgia, Alabama, Mississippi and Texas, and doubtless some of the Eocene 
deposits ill Arkansas and North Carolina belong to the same period. Underlying the 
“ Clilibornian ” in the south are a series of clays, sands, and lignites, or in other 
localities, more or less siliceous and impure shelly limestones known as buhrstones — 
the “ chalk hills ’’—.several hundred feet in thickness, whose exact equivalence it is 
not Jis easy to demonstrate as those of the overlying sand beds, but which appear to 
hold a position somewhat parallel to that of the London clay (Londonian), or to the 
upiKT (and lower?) Suessonian of France. The “ Buhrstone ” (Siliceous Claiborne of 
Ililgard) occupies a considerable portion of the southern Tertiary area, attaining its 
principal development in Alabama, Georgia and South Carolina. In Alabama and 
Mississippi, as best studied in those States, with a probable development of 200- 
;}()() or more feet, we find at the base of the Eocene, a series of interstratified clays, 
sands and lignites, my “ Eo-Lignitic,” which seem to represent the most ancient of 
our cis-Mississippi Tertiary deposits. It appears pi'obable that the oldest Eocene 
deposits occurring in New Jersey — those, for example, exposed on Shark River — 
belong here, and po.ssibly also the Piscataway and Marlborough beds of Maryland 
and tlie Pamunkey sands of Virginia, which I have claimed to be the probable 
equivalents either of the British Thanet sands (or those of Bracheux, France), or of 
''the British Bognor rock (lower I,ondonian). Not impossibly, however, they may 
prove to be the equivalents of a portion of the '‘Buhrstone.” Immediately overlying 
the “ Claibomian ” in Alabama, Mississippi and South Carolina, Avith a considerable 
development in Louisiana and Georgia, and evidently also, although not as yet 
distinctly marked out, in Texas and Arkansas, are the deposits that have been desig- 
nated the “Jacksonian,” .so named from the town of Jackson, in Mississippi, whence 
the fossils considered typical of this group were first obtained. In this series are 
included the so-called “white limestones” of many geologists, in which (and elsewhere) 
have been found, more or less abundantly, the remains of the Zeuglodon, the most 
distinctive fossil of the formation. No precise comparison between the fossils of this 
formation and those of correspondingly situated trans-Atlantic formations has as yet 
been institvited, and, therefore, it may perhaps be premature to assert with positiveness 
what the exact homcon represented by them may be. But as the beds occupy a 
position immediately overlying Avhat is generally considered to be the next highest 
