1881.] NATURAL SCIENCES OF PHILADELPHIA. 157 



An examination of the foregoing section shows almost conclu- 

 siveh' that the Eocene deposits of Alabama have a thickness of 

 very nearly 400 feet; and, indeed, I am informed by Dr. Smith 

 that there are good grounds for supposing that Tertiar}^ beds 

 exist in the northern part of the State, wliose position would be 

 still 150-180 feet below the Wood's Bluff marl bed. It will fur- 

 ther be seen that the Claibomian (or Claiborne proper, as chai'ac- 

 terized by the fossiliferous greensands) holds a position decidedly 

 near the top of the series, a position almost preciscl}' similar to 

 that occupied by the " Calcaire Grossier " (Parisian) of France, 

 and more properly Upper than Middle Eocene, which last it has 

 verj'' generallj^ been considered. What relation beds •• b " and» 

 " c " of the Claiborne Bluff holds to the sub-Claibornian (•' Buhr- 

 stone " in part) deposits of the Tombigbee River has not yet been 

 absolutely determined ; but there can probably be no legitimate 

 doubts that they represent, in a modified form, the upper 

 moiety of those deposits. Although the marked difference in 

 the lithological character of the strata of the two localities as 

 compared with each other (and indeed it must be confessed, this 

 is much greater than could have been reasonably inferred from 

 the genera] constancy of the deposits in this region) would seem 

 to militate against such a view, there is, nevertheless, sufficient 

 evidence, both stratigraphical and paleontological, to support this 

 conclusion. In the first place, by determining the position of the 

 buhrstone rock near St. Stephen's as immediatel}'' underl3'ing 

 the highly fossiliferous greensand laj-er, Tuomej^ has proved that 

 the two series of deposits (the Buhrstone on the Tombigbee, and 

 bed " c " on the Alabama) hold relatively the same position to 

 the true Claibomian, lying immediately below it. In the second 

 place, the argillaceous sti'ata at the base of Claiborne Bluff (bed 

 " 4 " of Hale's series) have been identified by Hale, both on litho- 

 logical and paleontological evidence (A. J. Science, new ser., YI, 

 p. 356), as occurring at Coffeeville Landing on the Tombigbee 

 River, about 14 miles north of St. Stephen's, what miglit very 

 readil}' have been expected from an inspection of the general la}' 

 of the different formations.^ Xo data are given relative to 



^ A line uniting Claiborne and Coffeeville Landing would mn almost 

 precisely parallel with the line marking the junction of the Cretaceous 

 and Tertiary deposits lying hence due north. The contour lines traced by 

 Tuomey would indicate a true dip west of the southerly line, and that this 



