The series has almost always a constant dip of two or three degrees to the north. Silicified trees are very commonly found strewn over the surface both near the base and high up in the series.
At a point about 14 kilometres north of Qasr el Sagha definite organic remains other than bone-fragments were for the first time met with in the series. Here a fragment of ochreous-coloured grit containing numerous specimens of a small Melania was picked up and similar rocks were afterwards found in situ. Calcareous grits and impure limestones occurred at the same spot, and one of the harder more compact bands of limestone was found to contain casts of Cerithium.
Also at a point 9 kilometres north of Qasr el Sagha hard grey limestones, generally compact and cherty, and sometimes semi-crystalline, are present, containing casts of Melania, frequently filled with calcite. These overlie variegated sandstones, and occur at about 40 metres below the basalt near the top of the escarpment.
Blanckenhorn has determined my fossils from these localities as follows:—
Melania nov. sp., allied to M. Nysti of the Oligocene.
Potamides scalaroides, Desh., an important guiding form of the Middle Beauchamp Sands of the Paris Basin, and thus Upper Eocene.
Potamides tristriatus, Lam., of the Parisian (Cerithium crispum, Desh.,) is nearly related to the frequent Middle and Upper Eocene C. perditum, Bay, between which, according to Cossmann, transitions exist.
Cerithium tiarella, Desh., of the Middle and Upper Eocene, but more especially in the latter.
Blanckenhorn considers these determinations as certain, and thus marking the complex as Upper Eocene, on the level of the “Beauchamp Sands” of the Paris Basin, and consequently of the Lower Headon Hill beds and Barton Clay of the South of England.
The following section was measured from the base of the series, 2½ kilometres N.N.W. of Qasr el Sagha, to the summit of the escarpments, 2 kilometres N.N.W. of Widan el Faras. The series has its maximum thickness at this point.