652 PROCEEDINGS OF THE BALTIMORE MEETING 



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 represent 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, un- 

 fossiliferous, but are now regarded as belonging unquestionably to the Lower 

 Cretaceous. 



Reference has already been made to the fact that the Magothy-Matawan- 

 Monmouth formations of the northern part of the Coastal plain are to be corre- 

 lated with the Black Creek-Peedee formations of North Carolina. It seems 

 equally certain that these find their counterpart in the Tuscaloosa-Eutaw- 

 Ripley of the eastern Gulf, with the exception of such portion hitherto referred 

 to the Tuscaloosa as is known to be of Lower Cretaceous age. 



Very little is known of the fauna of the earliest marine sediments commonly 

 referred to the Eutaw, although the few fossils found come from apparently 

 interstratified marine beds not unlike those in the Black Creek and -the Mago- 

 thy. It is also apparent that the fauna of certain strata of the lower portions 

 of what has been regarded as Ripley, on the Chattahoochie river, represents the 

 Black Creek and the Magotky-Matawan, but whether these beds should be con- 

 sidered Ripley or as representing part of an earlier horizon, and thus included 

 in the Eutaw, can only be determined by further investigations. 



It is largely a question, in any event, as to whether the term Ripley or Rip- 

 leyan shall be used in a broad way to include the beds containing both the 

 lower and upper faunas, in which case even the Eutaw would have to be re- 

 garded as Lower Ripley, or whether two formations are to be recognized to be 

 called Ripley and something else, either Eutaw or Tombigbee, as certain 

 stratigraphic and paleontologic facts suggest. Continuous sedimentation, with 

 gradual change in the character of the materials until the beds became wholly 

 or at least largely marine, doubtless continued during the life of these faunas 

 here, as in the other areas, and such facts as are available point to this conclu- 

 sion. Such being the case, the term Ripleyan might perhaps with greater pro- 

 priety be applied, as has been frequently done to the entire fauna, if it seemed 

 inadvisable to restrict it, in which event a new f ormational name would have to 

 be employed for the upper beds. It is evident that the greater part of the 

 deposits comprising the Tuscaloosa must of necessity be associated with the 

 Upper Cretaceous strata of the Gulf region, and a group term to include this 

 entire series of deposits would not be inappropriate. A final decision on these 

 points, as well as a satisfactory correlation of the Middle Atlantic with the 

 Eastern Gulf deposits must be deferred, however, until more is known of the 

 stratigraphy and paleontology of the latter region. 



When a comparison of the Atlantic Coast Cretaceous fauna is made with 

 that of the European Cretaceous we find that its general character is that of 

 the Senonian, and the view has been commonly held by invertebrate paleontolo- 

 gists that all of the marine beds of the Atlantic and Eastern Gulf coasts repre- 

 sent that epoch of the Cretaceous, with the possible exception of certain later 

 deposits in New Jersey which have been regarded by the writer and others as 

 of Danian age. Some even include in the Senonian all of the Upper Cretaceous 



