NEWTON : LOWER TERTIAEY MOLLUSCA OF THE FAYUIT. 63 



1901. Mr. Beadnell alluded to the above views of Dr. Elauckeiir 

 horu, but regarded the wliole of the Jebel el Qatrani Series as 

 resembling a fluvio-iuariue area similar to the Oligocene of Hampshire 

 I in England. 



1901. . The beds were again referred to bj- Mr. Beadnell and 

 assigned provisionally to the Oligocene period. 



1901. Mr. Beadnell next definitely recognized these rocks as 

 Upper Eocene for tlie beds below the basalts, and for those above 

 a Lower Oligocene age was suggested. 



1903. After further studies, Dr. Blanckenhorn still regarded the 

 beds as Upper Eocene. 



1905. In Mr. Beadnell's principal and final work the beds were 

 referred to as Upper Eocene or Bartonian. 



1906. Similar stratigraphical views to those finally published by 

 Mr. Beadnell were expressed by Dr. C. W. Andrews in his monograph 

 on the fossil vertebrates of the Fayum. 



1906. Dr. Oppenheim regarded the Jebel el Qatrani mollusca as 

 Ui^per Eocene or Lower Oligocene in liis monograph on the older 

 Tertiary shells of Egypt. 



1907. Professor Deperet noticed the nearly basal deposits of the 

 Jebel el Qatrani Series containing the vertebrates as of the Sannoisian- 

 Stampian stage of the Oligocene. 



1907. Dr. Oppenheim, contrary to Professor Deperet's views, 

 recognized the same beds as of Ludian age (Ludian Beds being above 

 the Bartonian and necessarily younger), but the upper beds of the 

 Jebel el Qatrani Series containing the mollusca were unreservedlj' 

 regarded as Eocene. 



1907. Professor Deperet again called attention to the subject by 

 supporting the Oligocene age for the vertebrates, an opinion followed 

 by nearly all the later writers on the vertebrate palaeontology of the 

 Fayum. 



1912. The Jebel el Qatrani or Fluvio-marine Series was regarded 

 by Dr. Dacque as of Lower Oligocene age. 



In the chief elements of this discussion it is obvious that we are 

 indebted to Dr. Blanckenhorn (who was assisted by Dr. Oppenheim) 

 as to the stratigraphical value of the mollusca occurring in the upper 

 or younger deposits of the Jebel el Qatrani Series. 



Later, however. Dr. Oppenheim monographed the shells as of 

 Upper Eocene or Lower Oligocene age, and subsequently the same 

 author somewhat changed his views, stating that the vertebrates were 

 of Ludian age, and that the mollusca were Eocene, without definition 

 as to the particular stage of that formation. It should be understood 

 that the Ludian strata follow the Bartonian, and that they are 

 variously regarded as topmost Eocene or the lowest Oligocene," such 

 rocks being also known as Priabouian. We can only assume, therefore, 

 although not definitely stated, that Dr. Oppenheim no longer regarded 

 these deposits as Bartonian but Ludian. 



The Jebel el Qatrani rocks, which succeed, without unconformity, 

 the Qasr el Sagha Series, show a total thickness of some 270 metre's, 

 the beds extending from the base near the north-west of Qasr el Sagha 



VOL. X. — JUNE, 1912. 5 



