52 . DR. GEANT BEY, 



111 the later Pleistocene it would appear that the Blue Nile 

 debouched into the lagoon of the isthnnis, Avhich at that time 

 of continental elevation was much more extensive than now. 



It is to this period that we must ascribe the Sahara Sea, 

 ^nd the large inland sea of Geikie, Avhicli included the Black 

 Sea, and Caspian, aiid a large tract of country to the west of 

 the Ural Mountains.'-' As long as these existed the rainfall in 

 Eg^ypt and in Arabia must have been excessive, and this 

 accounts for the manner in which the surfaces of the anortho- 

 site gneiss (diorite) and schist show such an amount of 

 wasting and disintegration. Professor Hull has also found 

 evidences of a chain of ancient freshwater lakes in the 

 Sinaitic ]-)einnsula that must date from this period, and that 

 disappeared when these inland seas dried up and the rainfall 

 €eased. 



At the close of the Pleistocene elevation, or in other words 

 in the early modern geological epoch, we find the Red Sea 

 shells at the Bitter Lakes quite like the recent shells.^" 



The ridge at Shaloof must have been at this time under 

 water as we may judge by the shells now to be seen in its 

 upper layer. Its elevation, therefore, is quite modern geo- 

 logically speaking, and the elevating process continues, 

 though slowly as measured by the geological clock. 



At a date more immediately preceduig the Prehistoric 

 Peri-od^^ the land of Egypt was higher than at present ; but 

 owing to the earth's shrinkage the Avhole country sank con- 

 siderably, thereby causing two fractures that are evident, 

 one along the Mokattam range from Cairo to Suez, and the 

 other along the present Valley of the Nile whereby a cle- 

 joression of upwards of 150 feet on the Libyan side took 

 place. 



Even at the present day, were the Nile to diy up, the sea 

 would again reach this ancient limit near Memphis along the 

 empty bed of the river. 



:\OTES. 



' One of tliese fossils was presented by Dr. (J rant Bey to the late 

 Professor Sir Richard Owen, who described it fully in the Quartcdt/ 

 Journal of tlie (Jeoloyical Soeieti/ for February, ISTT). It proved to be 

 the fossil skull of an Eocene Sirenian mammal, of the .same type as the 

 Llngony which .still exi.sts in the lied Sea. 



- There is abundant evidence of volcanic action in various parts of 

 Egypt, at Abu-Zabel near Cairo, at the Cataracts, and almig tlie Hed Sea 

 coast plutonic rocks are met with. 



^ These forests contain exogenous and endogenous trees. Several species 



