_The return journey from Baharia Oasis to Minia_ was made, as already mentioned, across the open desert, not following any road. The starting-point was the point on the southern scarp of the oasis, where the Farafra road leaves Baharia. Our observations give for the position of this point[25] lat. 27° 46′ 13″ N. long. 28° 32′ 47″ E. of Greenwich; height above sea level, 247 metres. The course was shaped so as to reach the village of Nasl Nadiub Lengat, whence the outward traverse had started, so as to give a closed polygon of survey-lines. The following topographical and geological notes were taken on the journey. The first 2½ kilometres of the way, going about S.S.E., lay over a plateau of sandy limestone, often mammilated and strewn with limonite-fragments. Sand-dunes of small size were passed on the left. An ascent was then made of some 35 metres on to a flat-topped ridge, consisting of white and yellow marls and clays, capped by a horizontal bed of hard brown calcareous grit, passing into brown crystalline limestone with calcite shell-casts. On this ridge, which is about 600 metres in width at the place seen, a turn was made so as to go almost due east. The descent from the ridge on the other side is on to a plain strewn with whitish-brown laminated and mammilated limestone and some limonite, and from the plain rise hills showing the same structure as the ridge just crossed. A camel-road running south was crossed 7 kilometres from the starting-point, and beyond this, the ground having gradually risen to the level of the brown calcareous grit, we came among numerous low hills; these consist of white chalk beds, capped by sandy greyish limestone and then by thick beds of harder greyish-white limestone, weathered grey on the surface. No fossils were seen here, but continuing the journey east, over uneven ground of white and greyish limestone of considerable hardness, a small hill was met with, at about 12 kilometres from the starting-point, and found to consist of limestone with _Nummulites_, and these foraminifera were found in great abundance a little further on. The finding of these forms, so distinctively Eocene, is important as showing that whatever the age of the limestones at the actual edge of the south part of the oasis may be, the beds forming the plateau only a few kilometres east of the oasis are, like those which form the top of the northern scarp, of undoubted Eocene age. The nummulites were visible in the rocks of the plateau till about 17 kilometres from the starting-point, none being noticed further on till the neighbourhood of the great sand-dunes was reached. At 25 kilometres a slight depression containing numerous hills of white chalk was entered. The floor of this depression, 267 metres above sea-level, is strewn with fragments of crystalline calcite, probably derived from veins or druses in the chalk. The beds here dip slightly to the south. About 3 kilometres further on the beds dip