576 PKOF. J. W. GKEGOKY ON [Nov. I9II, 



with the literature of Cyrenaica, he overlooked Admiral Spratt's 

 account of the geology of Derna and the identification of a num- 

 mulite from Mersa Susa by the late Prof. T. Hupert Jones. 



The most precise geological information regarding Cyrenaica was 

 given by Admiral Spratt * ; but, as it was an Appendix to a book on 

 Crete, it has been overlooked. He contrasted the jagged mountains 

 of Crete with the plateaux of Libya extending from Tripoli to the 

 Nile ; and he recognized the numerous sudden flexures of the coast, 

 as in the Syrtis, the Gulf of Salum, and at Has el Tin, as due to 

 faults. His most important contribution to the geology of Cyrenaica 

 was an account of the section at Derna, which he described as com- 

 posed of a lower series of white or cream-coloured limestones ' full 

 of nummulitic shells resembling those of Crete ' (op. cit. p. 377) ; 

 and this lower series, 250 feet thick, he described as passing 

 conformably upwards into yellowish marly sands or sandstone, 

 resembling the yellow sandstones of Malta and containing many 

 of the Maltese fossils. That Spratt's foraminifera were really 

 nummulites cannot be doubted, as one specimen, now in the 

 (Natural History) British Museum, was identified as the Lower 

 Eocene Nummulites perforata? 



The identification of nummulites from Cyrenaica having been 

 overlooked or discredited, Cyrenaica has been generally described in 

 recent years as composed of a sheet of Miocene and perhaps also 

 Pliocene limestones. This view was expressed by Dr. Giirich, 3 who 

 described the country as mainly Middle Miocene ; and he appears 

 to exclude the possible occurrence of Oligocene deposits by reference 

 to the existence of an important gap in this region between the 

 Eocene and the Miocene. Zittel 4 and Suess 5 both also accepted 

 Cyrenaica as Miocene. Suess referred to it, though doubtfully, as 

 belonging to the second Mediterranean stage — that is, Upper or 

 Middle Miocene. This view was based on the collections made by 

 Schweinfurth at Mersa Tobruk, on the coast of Marmarica ; and 

 in Suess's sketch-map (Joe. cit. fig. 41) the whole country is 

 represented as belonging to the Upper Mediterranean stage and 

 younger formations, while the later French edition by M. de 

 Margerie 6 includes a map after G. Holland, in which the country 

 is all marked as Middle Miocene. According to the last statement 

 on the subject, issued in 1907 by M. D. E. Pachundaki, 7 the 



1 T. A. B. Spratt, ' Travels & Eesearches in Crete' vol. ii (1865) app. iv, 

 pp. 375-80. 



2 T. R. Jones, ' Catalogue of the Fossil Foraminifera in the British Museum 

 (Nat. Hist.) ' 1882, p. 45. 



3 G. Giirich, ' Ueberblick tiber den geologischen Ban des afrikanischen Kon- 

 tinents ' Petermann's Mitteilungen, toI. xxxiii (1887) p. 261 & pi. xiii.. 



4 K. A. von Zittel, ' Beitrage zur Geologie & Palaontologie der Libyschen 

 Wiiste ' Palaeontograpbica, vol. xxx (1883) pp. xxvi-xxvii & exxxi. 



5 E. Suess, 'Das Antlitz der Erde' vol. i (1885) p. 465. 



6 ' La Face de la Terre ' vol. i (1897) pp. 459 (fig. 68) & 464. 



7 D. E. Pachundaki, ' Contribution a l'Etude Geologique^ des Environs 

 de Marsa Matrouh (Marmarique) ' Revue Internationale d'Egypte, vol. iv 

 (1907) p. 8. 



