500 B. Bulkn Neidon — Shells from Raised Beaches, Red Sea. 



lY. Pleistocene Shells fkom the Eaised Beach Deposits of 



THE Eed Sea. 



By E. BxJLLEx Newton, F.G.S., of the British Museum (Natural History). 



(PLATES XX-XXII.)i 



AN interesting collection of shells, numbering more than fifteen 

 hundred specimens, obtained by the officers of the Geological 

 Survey of Egypt from the raised beach deposits of the Red Sea, has 

 recently been examined by the writer at the request of Captain 

 Lyons, E.E., the Director-General of the Survey. 



With the exception of certain S2)ecimens collected by Dr. Hume 

 from the western shore of the Gulf of Akaba, this important 

 collection was acquired by Mr. Thomas Barron, F.G.S., from 

 various localities situated on the western side of the Red Sea and 

 the Gulf of Suez during the survey of that region in the years 

 1897-1898. 



The majority of the shells belong to modern species and are well 

 preserved, many of them retaining their original colour-markings 

 and other characteristic features. The species exhibit the true 

 Red Sea or Indo-Pacific facies, with a very slight commingling 

 of Mediterranean forms, a fact which confirms the work of most 

 previous observers, who recognize marked differences in the two 

 faunas. A few of the specimens are quite unknown in present seas, 

 whilst others date their origin from Miocene times, but as all are 

 accompanied by undoubted modern species they must be admitted 

 as their contemporaries in time. Among such may be mentioned 

 Aledryonia Virleti, Clilamys latissima, Chlamys Beissi, Pecten Vasseli, 

 LiOiopliaga Avitensis, Cassis Icevigata, etc. This association of 

 modern and extinct forms has already been observed by Professor 

 Mayer -Eymar, Dr. Theodore Fuchs, and others in deposits of 

 similar age near Cairo (Wadi Mellaha, etc.) and to the north of 

 Suez (Bitter Lakes, etc.). 



The marine portion of the terrace beds surrounding the Bitter 

 Lakes resembles the raised beaches of the Red Sea in possessing 

 a fauna of Indo - Pacific character, whereas the Cairo deposits 

 contain an assemblage of species bearing a large percentage of 

 Mediterranean or Atlantic forms : facts which indicate that in 

 former times the Mediterranean extended further southwards and 

 the Red Sea further northwards than now obtains. 



In dealing with the age of these deposits it seems apparent that 

 they should be regarded as Pleistocene on account of the large 

 number of recent species they contain, and the comparative scarcity 

 of extinct forms. This is in agreement with the views of most 

 authors, who, although under different designations, acknowledge 

 the same horizon, as, for instance, "Saharian" of Mayer-Eymar; 

 "Recente Ablagerungen (Pseudo-Sarmatischen Ablagerungen) " of 

 Fuchs ; and " Jiingere Meeresbildungen " of Fraas. It should be 

 mentioned, however, that Fraas only uses his term in connection 



1 These plates -n-ill apperr with Part II in the December number. 



