574 PKOF. J. W. GREGOEY ON [Nov. 19 I I, 



rises upon the northern border of the African coast, and extends from the 

 western shores of the gulph of the Great Syrtis as far as the kingdom of 

 Morocco ; and my observations upon the termination of the gulph demonstrate 

 that there exists no such connexion. But this does not prevent the calcareous 

 constitution of Mount Atlas from forming also the character of the Cyrenean 

 mountains. I am unacquainted with the Atlantic chain of mountains to the 

 west of Tripoli, but I have seen several specimens of the rocks between Tripoli 

 and Tunis, and they display the same character and formation.' l 



He recorded the presence in Cyrenaica of many fossils different 

 from the existing Mediterranean fauna, and he described some of 

 the fossils from the mountains as ' presenting in their fractures 

 the character of Ammonites.' 2 It therefore appeared possible, from 

 Delia Cella's statements, that Cyrenaica might have a foundation of 

 Mesozoic rocks containing Ammonites. 



The existence in Cyrenaica of Palaeozoic or pre-Palaeozoic cry- 

 stalline marbles seemed also possible. For, according to Delia Cella, 



1 the heart of these mountains consists of a compact chalk which has the usual 

 hardness of all kinds of marble ; and, though of secondary formation, and 

 bearing frequent traces of shells, its grain is fine and often glitters like saline 

 marble.' (Op. tit; p. 116.) 



The Italian traveller Camperio remarked 3 in 1882, that the 

 marble used for the statues at Cyrene might either have come from 

 the Greek islands or from the neighbouring mountains. The 

 statues, of which the British Museum has a valuable collection, 

 are of saccharoidal marble, and so also is the one specimen that I 

 have examined in the Louvre. Hence Capt. Camperio's suggestion 

 of the local origin of this material was consistent with the 

 occurrence of a Palaeozoic, or perhaps even older, formation in the 

 mountains of Cyrenaica. 



Hamilton, in 1856, described the coast-hills from the Wadi Nagr, 

 where the track to Cyrene leads on to the plateau, past Derna 

 towards Has el Tin, as composed of ' barren sandstone,' 4 and 

 Dr. Hildebrand 5 quotes Meier-Jobst as asserting the occurrence of 

 sandstone at Cyrene on the summit of the plateau. These reports 

 suggested that sandstones might play an important part in the 

 structure of Cyrenaica. 



The geological evidence connecting the Cyrenaican mountains 

 -with the Atlas was indefinite ; but it was supported by the con- 



i Paolo Delia Cella, ' Physician Attendant on the Bey ' : ' Narrative of an 

 Expedition from Tripoli in Barbary to the Western Frontier of Egypt, in 

 J.817, by the Bey of Tripoli ; in letters to Dr. Viviani of Genoa, by ... ; with 

 an Appendix, containing instructions for navigating the great Syrtis.' Trans- 

 lated from the Italian by Anthony Aufrere, Esq. London, 1822, pp. 165-66. 



2 Ibid. p. 165. The original of this passage is as follows :— ' Talvolta trovasi 

 guarnita di piccoli testacei lentiformi, che nella loro spaccatura presentano i 



. caratteri delle Ammoniti ' (Lettera xiii, p. 162). 



3 Camperio, ' Una Gita in Cirenaica' Esploratore, vol. vi, 1882, p. 16. 



4 James Hamilton, 'Wanderings in North Africa' 1856, p. 113. 



5 G. Hildebrand, ' Cyrenaika als Gebiet kiinftiger Besiedelung ' Bonn, 1904, 

 ,p. 86. 



