56 Berry: MEsSOzOIC FLORA OF ATLANTIC COASTAL PLAIN 
The Tombigbee sand member of the Eutaw formation represents 
transgressive marine deposits without land plants but with a 
marine fauna. To the southward the Tombigbee is overlain by 
the Selma chalk—a lithologic and not a chronologic unit. In 
western Tennessee the time interval corresponding to the lower 
Selma chalk is represented by the Coffee sand member of the 
Eutaw formation which at a few localities in Tennessee contains a 
considerable number of fossil plants. The Coffee sand in Tennes- 
see is overlain by a calcareous clay representing a thin tongue from 
the thick mass of Selma chalk to the south. Overlying the Selma 
in the Tennessee area, the Ripley formation is differentiated into 
four members to which the names Coon Creek, Ferruginous Sand, 
McNairy Sand and Owl Creek have been applied. All of these 
are littoral or marine deposits with in some cases abundant marine 
faunas. 
All but thirteen of the 135 species of fossil plants recorded 
from the Ripley formation in the following pages come from 
Eocene 
Ripley formation Owl Creek member 
oe McNairy Sand member 
Eine lh Ferruginous Sand member 
Coon Creek member 
Selma chalk 
Tombigbee sand member of the Eutaw formation 
Basal beds of the 
Eutaw formation 
Tuscaloosa formation 
Paleozoic 
shallow water lenses of plastic clay in the McNairy sand member. 
These clay lenses represent accumulations of fine material in 
estuary or coastal lagoon waters with a well forested shore near 
at hand. The accompanying diagram shows the stratigraphic 
units and their general relations in the Mississippi embayment 
ese 
