Vol. 60.] THE DISTRICT SURROUNDING THE DARDANELLES. 285 



both these species in the number of vertebrae ; and it also agrees 

 with D. humilis in the characters of the ridge-scutes and the 

 extent of its median fins. In these species, however, the head is 

 smaller, and the dorsal tin farther forward than in the new form ; 

 while D. vectensis is also easily distinguished by the greater extent 

 of its anal fin, which comprises sixteen or seventeen rays. 



[A. Smith Woodward.] 



Formation. — Miocene (lacustrine Sarmatian). The matrix 

 is a light-coloured calcareous sandstone. 



Locality. — Found on the surface of the ground at the southern 

 end of Gorgona Dere, near Sarkeui (Sea of Marmora.) 



Miocene (Vindobonian = Helvetian-Tortonian) . 



The oldest marine Miocene shells that have been determined 

 belong to the Helvetian-Tortonian Period, or Vindobonian (of 

 Deperet), and were obtained from Eregli andFakirma in the Gulf of 

 Xeros ; from near Myriophyto Dere, about 700 feet above sea-level ; 

 and from Tzenguerli Dere. 



Those from Eregli include : — Alectryonia Virleti, Deshayes ; Ostrea 

 lamellosa, Brocchi ; Pecten aduncus, Eichwald ; Anadara diluvii, 

 Lamarck, which is also found at Fakirma. 



From Myriophyto Dere, 700 feet above sea-level: — Ostrea eras- 

 si ss 'ana. 



From Tzenguerli Dere : — Ostrea gingensis (Schlotheim). 



These are species characteristic of the Vindobonian (= Helvetian- 

 Tortonian) rocks of countries skirting or near the Mediterranean, 

 such as Egypt and Northern Africa, Greece, Persia, etc. The 

 specimens of Pecten aduncus, Eichwald, are well interpreted by 

 Fuchs's figures of examples from Egypt. 1 



Oligocene (Aquitanian & Stampian). 



Some light-brown to drab-coloured sandstones have been obtained 

 from north-west of Beyendi-keui and south-east of Lala-keui, 

 showing dicotyledonous leaf-impressions, one of which appears to 

 resemble Myrica lignitum, as identified in the British Museum 

 (Natural History), a form common to the Parschlug Beds of Styria, 

 and of Aquitanian age. It is, therefore, probable that these plant- 

 remains belong to the same horizon. 



The presence of Stampian Beds (or Tongrian of older authors) at 

 Masatly and north-west of Keshan, etc., is much more certain, 

 however, as the characteristic shell Corbicula semistriata (= Cyrena 

 subarata, Bronn) has been determined, associated with Melanopsis 

 cf. fusiformis and AntJrracotJierium-teeth. (of small size, and possibly 

 related to A. cf. minus, a form characteristic of the Hempstead or 

 Stampian Beds of the Isle of Wight). The Anihracotheriam-remams 



1 ' Beitrage zur Kenntniss der Miocanfaima ^gyptens, &c.' in 'Palreonto- 

 graphica' vol. xxx (1883) p. 54 & pi. xix, figs. 1-5. 



