6;o SCIENCE PROGRESS 



has been visited on several occasions by Mr. Beadnell on behalf 

 of the Egyptian Geological Survey, and by the writer for the 

 British Museum. The large collections made on these occasions 

 have been described and figured in the Catalogue of the Tertiary 

 Vertebrata of the Fayum, published last year. 



The Fayum is a province of Egypt lying about sixty miles 

 south of Cairo, to the west of the Nile valley, from which it 

 is separated by a strip of desert traversed by a canal, through 

 which practically the whole water supply of the district passes. 

 It consists mainly of a depression in the desert, the lowest 

 portion being occupied by a large lake of brackish water — the 

 Birket-el-Qurun — which is, in fact, the remnant of the much 

 larger body of water described by Herodotus under the name 

 Lake Mceris. From early historic times, for various reasons, 

 this lake has been decreasing in size, and there are to-day 

 numerous evidences of its former extent, such as traces of the 

 old shore lines marked by stumps of tamarisk bushes, which 

 then, as now, fringed its margin ; but still more eloquent 

 witnesses of its former size are the ruined towns and temples, 

 now lying in the desert far from any water supply. To the 

 north of the lake the land rises in a succession of escarpments 

 separated by plains of varying width, to a height of about 

 340 metres above the sea ; the surface of the lake itself being 

 about forty-four metres below the level of the Mediterranean. 

 The lower escarpments are carved in beds of Middle Eocene 

 age, the higher in the Upper Eocene, the actual summit of the 

 escarpments being formed by the outcrop of a sheet of inter- 

 bedded basalt, above which are the gravelly fluvio-marine 

 Oligocene beds which form the undulating surface of the high 

 desert stretching away towards the north. 



The vertebrate remains are found some distance to the north 

 and west of the lake, and they occur at several horizons, the 

 lowest being near the bottom of the Middle Eocene. At this 

 horizon the beds are almost exclusively marine, and the only 

 vertebrates found are aquatic types, the most interesting being 

 a primitive toothed whale, Prozcuglodon. The next bone-bearing 

 beds are at the top of the Middle Eocene, and consist of a series 

 of marine and estuarine deposits, which contain the remains of 

 both marine and terrestrial mammals, the most important of the 

 latter being Mceritherium, the earliest known Proboscidean, and 

 Barythcrium, a remarkable ungulate of which the affinities are 



