T. Barron — Miocene Beds between Cairo and Suez. 605 



'-likely than that some of the silicified tree trunks were rolled in 

 from the ridges surrounding these basins? Any silicified wood 

 seen by the writer in Miocene beds has always been much broken 

 up, and presented the appearance of having been moved after 

 silicification rather than that of petrifaction in situ. One has only 

 to compare the trees in the Petrified Forest with these to see the 

 difference. 



According to Blanckenhorn ^ the Lower Miocene is a fluvio-marine 

 formation characterized in Mogara by Mytilus aqidtanicus, Cytherea 

 erycina, and Anthracotherian bones. The Helvetian, on the other 

 liand, has a numerous pecten and oyster fauna associated near its 

 base with a more shallow-water assemblage of forms. In fact, 

 the Lower Miocene is essentially a fluvio-marine formation, while 

 the Helvetian is marine. 



This author, in his Table of Miocene Strata in Egj'^pt and Syria,^ 

 gives the following fossils as characteristic of the Lower Miocene 

 of Mogara : — 



Scutella Zitteli, Beyr. ; Mytilus aquitanicus, M.E. ; Lucina ornata, 

 Ag. ; Zucina columbella, Lam. ; Cardium cf. taurinnm, Micht. ; Venus 

 o'vata, Penn. ; Cytherea erycina, L. ; Corbula revolutn, Brocc. ; Teredo 

 Mediterranen ; Tarritella ierehralis, Lam. ; T. cnlTiedralis, Brongn. ; 

 Crepidula coclilearis, Bast, ; Golems chinensis, Lara. ; together with 

 fossil wood, Podocnemis, Trionyx, Crocodiliis, Brachyodus, and 

 Rhinoceros. In addition to these the following are given in the table of 

 fossils for the Miocene ^ as occurring only in the Lower Miocene : — 

 Cupularia cf. urciolata, Lara. ; Anomia ephippinm, var. squamula, L. ; 

 Cardita rufescens, Lam. ; Diplodonta rotundata, Mont. ; Cardium 

 jpaucicostatum. Sow. ; Dosinia Adansoni, Phil. ; Tapes Basteroti, 

 Desh. ; Tellina cf. exigua, L. ; Ervilia pusilla, Phil. ; Mactra 

 burdigalensis, May. ; Corbula Basteroti, Horn. ; Tugonia anatina^ 

 Gmel. ; Oliva clavida, Lara. 



It is now possible to proceed to the description of the beds for 

 which a Lower Miocene age is claimed. 



Between 8 and 9 kilometres east of Abbassia there occurs a series 

 of ridges of gritty limestone, calcareous grits, and ferruginous, 

 calcareous, sandstones and grits, bounded on the south by a thin 

 sheet of basalt, and faulted down on the north along the side of 

 the Old Post Road to Suez. They persist to the north of this 

 fracture, but are much masked by gravel and downwash. This 

 series of beds lies in a shallow basin, and is unconformable to the 

 basalt and overlaps on it. After examining these beds at different 

 places and collecting the fossils, the following succession was made 

 out, although the thicknesses cannot be taken as absolute, the beds 

 never being found in an escarpment of any height to allow of 

 a careful measurement being: made : — 



1 Loc. cit., pp. 54-5. 



2 Loc. cit., p. 53. 



3 Loc. cit., pp. 106-112. 



