32G Correlation of the Upper Cretaceous Formations 



nolia hollicki, Myrica longa, Myrsine gaudini, Podozamites marginatus, 

 Sequoia heterophylla and Widdringtonites reichii, and it is obvious that 

 the floral evidence furnishes strong confirmation of that derived from the 

 stratigraphic and structural facts, all of which point to the synchroneity 

 of the Magothy formation with the middle and upper portions of the Tus- 

 caloosa formation. The basal beds of the Eutaw formation in western 

 Georgia and at a few localities in Alabama have furnished a considerable 

 flora with which the Magothy of Maryland has fourteen species in com- 

 mon. These include Andromeda novce-ccesarece, Doryanthites cretacea, 

 Ficus crossipes, Ficus krausiana, Magnolia capellinii and Salix flexuosa. 

 While the evidence furnished by the floras is less complete than that 

 furnished by the abundant faunas, as far as it is available it confirms 

 the mutual relations of the Magothy, Black Creek and Eutaw formations. 

 The earliest fauna of any significance for wide correlation in Maryland 

 is that of the Mortoniceras subzone of the Matawan. Mortoniceras has not 

 been recognized in the Carolinas, but it has been found by Stephenson at 

 several localities from western Georgia to northern Mississippi, where it 

 characterizes the upper part of the Eutaw formation. In addition to 

 the common and diagnostic Mortoniceras element, Liopistha altemata is 

 a form restricted to this zone throughout its wide distribution. Other 

 common forms of less stratigraphic significance are Yoldia longifrons, 

 Crassatellina carolinensis, Baculites asper, and Placenticeras placenta. 

 The later -fauna along the Chesapeake and Delaware Canal and that of 

 the Western Shore of Maryland are probably synchronous with that 

 portion of the Exogyra ponderosa zone (Lower Selma-Ripley) lying 

 between the Mortoniceras subzone of Stephenson and the Exogyra costata 

 zone (Upper Selma-Eipley). The Chesapeake and Delaware Canal fauna, 

 however, is very local in character and probably represents only a part 

 of the time interval covered by the southern fauna. The typical and 

 diagnostic Exogyra ponderosa was apparently largely restricted to the 

 South Atlantic waters. The species occurs in the Middle Atlantic area, 

 but it is neither so ponderous nor so common as it is farther south. The 

 common Exogyra in the Camp Pox oyster bank is E'. cancellata, a species 



