THE PATUXENT FORMATION. 193 



clays), Arundel (clays, lignites, carbonate of iron concretions), and Pat- 

 apsco (variegated clays, sands) formations occur. The organic remains 

 consist for the most part of dinosaurs and plants. Lull, who has recently 

 studied the former, and Berry, who has been engaged in an investigation of 

 the latter, are agreed that they are of Lower Cretaceous age, so that the 

 earlier questionable reference of the Patuxent and Arundel formations to the 

 Jurassic is now abandoned. Farther southward in North Carolina is the Cape 

 Fear formation (arkosic sands, clays), so called by Stephenson, which is 

 evidently continuous with the Patuxent formation, although the basal beds 

 of the Coastal plain are transgressed by later formations in southern Vir- 

 ginia and northern North Carolina. No fossils have been found in the Cape 

 Fear formation, but the strata are similar lithologically to the Patuxent 

 farther north and unlike the Arundel and Patapsco." 



The name "Cape Fear" formation, proposed for the North Carolina 

 deposits, is now regarded as a synonym of Patuxent. The formation has 

 also been recognized in the "Hamburg beds" of South Carolina. 



The senior author of tliis report in discussing the correlation of the 

 Atlantic Coast Lower Cretaceous formations with those of the Gulf says:" 



"A correlation of the Cretaceous deposits of the Atlantic coast with those 

 of the eastern Gulf cannot be in all instances satisfactorily made, since the 

 Gulf Cretaceous series has never been worked out in detail, and much yet 

 remains to be done in the determination of the range of the species. Strata 

 hitherto called Tuscaloosa are found at the base of the Cretaceous series, in 

 eastern Alabama as well as in Georgia, which must be regarded as identical 

 with the Patuxent-Cape Fear formations of the Atlantic border. There is a 

 marked unconformity at the top of the beds, and deposits supposed to repre- 

 sent the Eutaw, or possibly in part the Tuscaloosa farther west, are found 

 above. Little is known regarding the western extension of these lower beds, 

 although it is possible that they may be found beneath the surface in central 

 Alabama, and perhaps farther westward. These older beds are, so far as 

 known, unfossiliferous, but are now regarded as belonging unquestionably 

 to the Lower Cretaceous." 



There is little doubt therefore but that the Patuxent formation is a 

 physicially continuous deposit from northern Delaware through Maryland, 

 Virginia, North Carolina, South Carolina, and Georgia to eastern Alabama. 

 Determinable fossils have only been found in the northern part of the district 

 but further investigation may show their presence in other areas as well as 

 in Maryland and Virginia. Among deposits containing a similar flora 



albid. pp. 651. (i52. 



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