The study of Egyptian geology during the last few years has thrown a flood of light on the former extension of the Mediterranean southward in Miocene times. Th. Fuchs, in examining the rich collections from the Cairo-Suez desert and the oasis of Siwah, recognized that the Miocene strata had a close resemblance to those of the Vienna Basin, and corresponded to the Grunder Beds at the base of the second Mediterranean stage, or the lower portion of the Middle Miocene. Later L. H. Mitchell, when studying the neighbourhood of Ras Jemsa and Jebel Zeit in 1887, obtained a number of large oysters, which Meyer-Eyinar recognized as Ostrea crassissima and Ostrea giganlea, and which were regarded as proving the existence of strata of Upper Miocene age along the western border of the Suez Gulf. From these results Blanckenhorn concluded that the Gulf of Suez must have been a Mediterranean bay in Miocene times, and further noted (Zeitsch. Deutsch. Geol. Gesell., Band liii, 1901, p. 79) that characteristic Miocene Pectens, viz. Pecten Sub-Malvinœ, occurred in the collection made by Barron at Abu Sha'ar. He further formed the opinion that all the marine Miocene strata in Egypt were of the age assigned to them by Fuchs (see also Barron & Hume, “Miocene Rocks in Eastern Desert,” Memoir of Egypt. Geol. Surv., 1902, pp. 159–165).