40 Bulletin 4 154 



there was a considerable time interval between the close of Creta- 

 ceous deposition and the beginning of Eocene deposition in the 

 Mississippi basin, and that wherever good contact exposures are 

 found, there may be found on careful study, ample evidence of 

 nonconf ormability . 



Correlations made. 



The following tables show in a general way the writer's ideas 

 regarding the probable stratigraphic relationship of the various 

 Midway beds heretofore described. Particular attention should 

 be given to the fact that it is the medial portion of the stage only, 

 that has generally been referred to by Alabama geologists as 

 Midway. The lower beds were usually referred to the Cretaceous. 

 Langdon however met the latter on the Chattahoochee river and 

 correctly referred them to the Midway Eocene, though unfortu- 

 nately he supposed them to be the outgrowth of the ' ' Turritella 

 rock" of central Alabama. 



Again, the " Turritella rock" of Mississippi and Alabama are 

 probably 100 feet apart strati graphically and hence when beds 

 are so designated, it should be stated what locality is referred 

 to; better still, such names should be abandoned. So far as 

 now appears there is a general similarity between the fossils of 

 this stage and those of the basal Eocene of Europe, yet specific 

 identities are rare. There is however a much closer affinity be- 

 tween our fauna and that of the so-called Cretaceous (really 

 Eocene) of Maria Farinha, eastern Brazil.* No one, at all 

 familiar with our Midwa}^ fauna can fail to see the close affinities 

 or perhaps identity with our species of Harpa [Pseudolivd] dechor- 

 data White, Calyptrophorus chelo7iitis White, Fasciolariaf \Mazza- 

 lhia\ aaitispira White, Turritella sylviana Hartt, Nautilus \En- 

 climatocerasf'\sowerbyanus White non d'Orb. , Gryphcea trachyoptera 

 White, Cuadlcsa hartii Rathbun, Cardita morganiajta Rathbun, 

 C. wilmothii Rathbun, et al. , 



Dr. White seems to have followed the generally accepted views 

 of the field workers in Brazil and called the fossiliferous beds of 

 various horizons Cretaceous. Long ago the writer suggested to 

 Mr. Stanton of the U. S. Geological Survey that some of the 

 "Cretaceous" material from this river Maria Farinha was to all 

 appearance Midway Eocene. He agreed that it had no traces of 

 Cretaceous features. 



*Contr. Pal. Brazil, C. A. White, 1888, vol. vii, Archivos do 

 Museu Nacional do Rio de Janeiro. 



