Reports and Proceedings — Geological Society of London. 235 



(1) The Geology of Cyrenaica. By John Walter Gregory, D.Sc, 



F.R.S., E.G.S., Professor of Geology in the University of 



Glasgow. 

 According to the scanty evidence available in 1908 regarding 

 Cyrenaica, which Hildebrand described in 1904 as " heute noch so 

 gut wie nnbekannt", the country might be interpreted as a fragment 

 of a mountain-loop, an off -branch from the Atlas, or as a plateau of 

 Miocene rocks. 



In a journey across the country the author found that it was 

 a plateau of Lower Kainozoic Limestones, which are classified as 

 follows : — 



Oligocene Cyrene Limestones. 

 (Aquitanian) 



!Slonta Limestones = Priabonian. 

 Derna Limestones = Moqattam Series of Egypt. 

 Apollonia Limestones = Libyan Series of Egypt. 

 Some Miocene limestones occur in places on the plateau, and lying against 

 its western foot. 



These rocks are all limestones, containing very little clastic material. 

 They must have been deposited in a clear sea, at depths ranging down 

 to nearly 1,000 fathoms. 



Intervals of shallow sea are indicated by some limestone con- 

 glomerates and a band of coral-reef limestone. The country was 

 uplifted in later Miocene times, and was then part of a wide land 

 which included Crete and occupied the site of the iEgean Sea. This 

 land was broken up by great subsidences, which left Cyrenaica as 

 a horst bounded by fault-scarps on the north and west. Eastwards 

 the country sinks by a slight dip and a succession of faults, until the 

 Miocene limestones, which occur on the plateau in Cyrenaica, are at 

 sea-level on the coasts of Western Egypt. Cyrenaica may thus be 

 regarded as part of the western limb of the geosyncline of Western 

 Egypt. 



The formation of the river-valleys probably began during a period 

 of wetter climate than the present, but there is no evidence of any 

 appreciable change in the climate or water supply since the date of 

 the Greek and lloman colonization. 



(2) Notes on the Kainozoic Mollusca. By Richard Bullen Newton, 



E.G.S. 



The author determines a number of mollusca which are recognized 

 as belonging to various members of the Kainozoic System, namely, 

 post-Pliocene, Helvetian-Tortonian or Vindobonian, Aquitanian, 

 Priabonian, and Lutetian. The most abundant of the post-Pliocene 

 series is Cerastoderma edule, a species largely distributed over Northern 

 Africa and the Mediterranean countries generally. Among the 

 Helvetian-Tortonian forms are Alectryonia cf. virleti and Strombus 

 cf. coronatus — well known in North African rocks of this age, as well 

 as in those of other Mediterranean regions. 



The Aquitanian shells present a relationship to the ' Schioschichten ' 

 fauna of Northern Italy, and consist mainly of Pectinoid species, such 

 as Pecten vezzcmensis, JEquipecten cf . pasinii, and Spondylns cisalpimis, 



