VIU 



INTEODUCTION. 



lowest is best developed towards the western end of the lake, running parallel with and 

 at a short distance from the northern shore ; this is composed of Ravine beds, Birket- 

 el-Qurun series, and the lower part of the Qasr-el-Sagha beds. The Eavine beds are, 

 for the most part, obscured by the overlying lacustrine deposits. The next main 

 escarpment is seen rising very steeply in the middle distance ; it is composed of the 

 higher beds of the Qasr-el-Sagha series. To the north of this, and separated from it 

 by a succession of broad terraces some kilometres wide, is the magnificent range of 

 cliffs, the Jebel-el-Qatrani, composed of the upper beds of the Fluvio-marine (Upper 



S. 



Dime. 



28 



Suiface of ancient 

 LakeNasris, 27-7im. 

 abouefiresertsea level. 



H on jjOntal Scaler 



.J kilometres. Heights in metres above sea levef. 



Section (from north to south) showing the succession of beds on the north of Birket-el-Qurun. (Eeduced 

 from part of the section on pi. xxii. of H. J. L. Beadnell's Eeport on the Topography and Geology of 

 the Fayum Province : Survey Dept., Cairo, 1905.) 



a. Lacustrine clays ; 2. Lower Oligocene ; 3. Interbedded basalt sheet ; 4. Upper Eocene (Pluvio-marine) ; 

 5. Qasr-el-Sagha series ; 6. Birket-el-Qurun series ; 7. Ravine Beds. 



Eocene) series, and capped by a thick bed of basalt, which Mr. Beadnell regards as 

 occurring at the junction of the Eocene and Oligocene beds. This upper range of 

 cliffs practically marks the northern edge of the depression, and beyond it comes the 

 •high undulating plateau of brown pebble-strewn desert, composed mainly of fluviatile 

 beds of Oligocene age, in which so far no vertebrate remains have been found. 

 Throughout the whole series the beds dip very gently (2° or 3°) towards the north, and 

 have been subjected to very little faulting or other disturbance. 



The following Table shows the succession of strata composing the country to the 

 north of the lake, together with a list of the vertebrate remains at present known 

 from the various horizons : — 



