Vol. 67. J DURING THE CRETACEOUS AND EOCENE PERIODS. 129 



according to the nature of the Danian "White Chalk and the 

 presence or absence of shales. Its other general features are the 

 great development of phosphatic beds in the Canipanian Series and 

 the complete dominance of sandstone during the Cenomanian and 

 Turonian epochs, no fossiliferous strata of these ages having been 

 recorded south of latitude 27° N. This phosphatic Cretaceous 

 belt sweeps from the hills near Gebel Zeit in a southerly and 

 south-westerly direction, crossing the Nile between Esna and Edfu. 

 and reappearing in the northern portions of Kharga and Dakhla 

 Oases. 



V. The Southern Cretaceous Type. 



A fourth facies was recognized during my expedition of 1908 in 

 the extreme southern portions of Egypt : especially at the Oasis 

 of Dungul, near Kurkur Oasis, and on the great Arbain road 

 south of Kharga. In these regions the Danian strata are, in the 

 main, a compact white limestone containing simple corals of the 

 Coelosmilia type, while the shales play a subordinate part. The 

 most noticeable change is in the character of the Campanian strata, 

 which, instead of being phosphatic or fish-bearing, are characterized 

 by a remarkable development of small sea-urchins, large Turritellce, 

 and a great variety of univalves recalling the Red Sea fauna of 

 the present day. They are noticeable for their marked yellowness, 

 and are a conspicuous feature wherever observed. The sea-urchins 

 which I collected have been recently described by M. R. Fourtau 1 

 under the names of Dorocidaris chercherensis {op. cit. p. 96), 

 Boihriopygus schweinfurthi (from Dungul, p. 104), and Gito- 

 lampas fallax (from Dungul and Um Shersher, pp. 107-15), the 

 last-named being extraordinarily abundant at Um Shersher, on the 

 Arbain road. 



VI. Summary of Cretaceous History in Egypt. 



We are now able to trace the sequence of Cretaceous history in 

 Egypt, both by modifications in the stratigraphical series and by 

 variation in its lateral distribution. Five phases are recognizable, 

 exclusive of those noted in Syria, where the whole of the Upper 

 Cretaceous appears to be represented by limestone. The five phases 

 are as follows : — 



(1) The North Egyptian type, in which the whole of the 

 beds, from the Danian to Cenomanian, are represented by lime- 

 stones ; while the Cenomanian marls and limestones are highly 

 fossiliferous, Hemiaster sp. and various exogyroid forms of oysters 

 being dominant. The Nubian Sandstone is, in its entirety, older 

 than the Cenomanian. 



(2) The Wadi Qena type, in which the Upper Cretaceous 

 series is subdivided by bands of sandstone, presenting features 

 regarded as characteristic of the Nubian Sandstone. The Danian 



1 ' Description des Echinides fossiles ' Mem. Inst. !&gypt. vol. vi, fasc. ii, 

 December 1909. 



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