Further south, on the west side, a very dissimilar succession was found to that on the north. Here at a distance of 20 kilometres from the oasis wall, at a point 30 kilometres north-west of Ain el Haiss, the uppermost member of the Cretaceous, the White Chalk itself, is overlain by a hard gray crystalline limestone containing an abundance of _Nummulites_ and _Operculina_, with _Lucina_, _Fusus_ and _Natica_. The actual junction of the two series is here difficult to detect, as the White Chalk is itself altered in its upper part into a hard gray crystalline limestone, simulating the Eocene beds themselves, and there is little difference of dip between the two series. The following foraminifera have been determined from this locality by Mr. F. Chapman:—[52] _Textularia? gramen_ | _N. discorbina_ | _Globigerina bulloides_ | _N. sub-discorbina_ | _Operculina complanata_, | _Orbitoides_ (_Discocycloides_) var. _discoidea_ | _dispansa_ (_O. dilabida_, Schwager). | _Nummulites gizehensis_, | var. _Pachoi_ | | _N. curvispira_ | Within the synclinal fold at one point (Plate VII), 17 kilometres north-east of Ain el Haiss, Eocene echinids and nummulites were found, but the beds from which they had weathered had been almost completely removed by denudation. The echinids have been recognized by Blanckenhorn as the following:— _Porocidaris Schmedeli_. _Echinocyamus luciana_. _Sismondia Sæmanni_. The following two species of nummulites have been determined by Chapman:— _Nummulites Beaumonti_. _N. sub-Beaumonti_. [Sidenote: Beds of east side of depression.]