64 PROCEEDINGS OF THE MALACOLOGICAL SOClETr. 



to the summit of the escarpment, not far from the noith-westera area 

 of Widan el Faras. 3*Jr. Beadnell has numbered the beds from 1 to 

 54, the latter being near the base of the series and therefore the oldest. 

 The more important of the fossiliferous bands are No. 49, where 

 Palaomastodon and other associated vertebrates occur; No. 15, con- 

 taining the estuarine mollusca Unio, Lanistes, Tarritella, etc. ; and 

 No. 7, bed with similar estuarine shells as in No. 15, with, however, 

 the addition of the marine shell Plenrotoma ingens. Some further 

 mollusca of the same habit were obtained from about 14 kilometres 

 north of Qasr el Sagha, these being regarded by Mr. Beadnell as on 

 the same horizon of bed No. 15. As previously stated, the more 

 estuarine shells from these deposits were determined by Dr. Blancken- 

 horn as Bartonian and on the same horizon as the ' Beauchamp Sands' 

 of the Paris Basin. 



According to Mr. Beadnell the Jebel el Qatrani Series consist of 

 variegated sands and sandstones, with alternating beds of clay and 

 clayey marls, in contradistinction to the older Qasr el Sagha Beds 

 below, which are characterized by ever-recurring bands of limestone. 

 The Jebel el Qatrani vertebrates are found very low down in the 

 series, whereas the estuarine shells are located a hundred or more 

 metres higher up, in the same section ; it follows, therefore, that the 

 vertebrates were first deposited and must of necessity be the most 

 ancient. These vertebrates consist more exclusive!}^ of the remains of 

 terrestrial mammals, while those of the Qasr el Sagha Series are 

 mostl)' marine and estuarine, with only a few land mammals. Such 

 difference in facies, together with the lithological variations noticeable 

 in the beds themselves, have suggested the succeeding age of Bartonian 

 for the Jebel el Qatrani vertebrates. 



Turning for a moment to the Qasr el Sagha vertebrates, we find 

 that they occupy a very high position in the section made by 

 Mr. Beadnell of these beds, which are composed of thirty divisions, 

 the fossils being restricted to beds 16, 17, 9, 7, and 2, in ascending 

 order. The numerous mollusca occurring both above and below and 

 throughout this series of deposits are referred to the Upper IMokattam 

 horizon of Egypt, which is included in the Lutetian or Middle Eocene 

 formation of Europe, some of the species occurring in Anglo-Parisian 

 rocks of that age. Among the more characteristic shells are Alectri/ouia 

 Ciot-bei/i, Exogy7'a Fraasi, Carolia placimoides, Macrosolen Holloivaysi, 

 Spondylus Egtjptiaais, Turritella transitoria, Mesaliafasciata, Cerithium 

 lamellosum, Naticina dehilis, Lanistes antiqmis, etc. There has been 

 no hesitation hitherto as to these Upper Mokattam Beds of Qasr el 

 Sagha belonging to the Lutetian or Middle Eocene Series, and yet 

 quite recently Dr. Dacque, before referred to, considered that tliey 

 belong to the Upper Eocene. There seems to be little diificulty, 

 therefore, in accepting the Lutetian age for these beds, more especially 

 when it is known that shells like Alecfryonia Clot-leyi and Carolia 

 placunoides, which are found above and below the strata containing 

 the vertebrates, are also of frequent occurrence throughout the section, 

 besides being met with in rocks of the same age in the Mokattam 

 district and in the neighbouring country of Tunisia. 



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