Vol. 58.] PETROLEUM-DEPOSIIS IN EUROPEAN TURKEY, 151 
These are included in a tract of country about 24 miles wide in 
a north-and-south direction, bounded on the west by the alluvial 
valley of the River Maritza, and on the south by the northern 
shore of the Gulf of Xeros; and in a littoral strip about 4 miles wide 
skirting the northern coast of the Sea of Marmora for about 32 miles, 
from abreast the head of the Gulf of a to Ganos, opposite 
the western end of Marmora Island. 
Hochstetter remarks (op. cit. p. 387) that 
‘this much, at any rate, can safely be derived from Viquesnel’s account, that 
the core of this coastal chain of mountains is formed of old crystalline rocks 
(Viquesnel indeed generally mentions “terrain de transition”) and chiefly ot 
rocks of the “ phyllite-zone” which are enveloped and overlain by Eocene 
Nummulitic limestones and sandstones, and by late Tertiary sandstones, 
limestones, clays, and mars.’ 
His map accordingly shows a large extent of ‘ pro-zoic’ clay- 
slate (phyllite) which, se far as I can ascertain, has no existence, 
the area being occupied by Eocene strata and contemporaneous or 
younger volcanic rocks. It is true that Viquesnel often suggests 
* terrains de transition,’ but always with considerable reserve, and 
Vicomte d’Archiac, at the commencement of the description of fossils 
(* Voyage dans la Turquie d’Europe’ vol. ii, 1868, p. 450) says :— 
‘We have not found, in the collection made by Viquesnel of fossils from 
Thrace, a single specimen belonging to transitional or even to old Secondary 
faunas. The only ones that denote the existence of late Secondary rocks are 
very few in number and come from two different localities.’ 
The lowest beds that I have seen are thinly-bedded hard blue 
coralline and softer brown Nummulitic limestones of Lutetian 
age. These crop out at the village of Vernitza (about 9 miles north- 
east of Ibridji on the Gulf of Xeros), where they show a north- 
westerly dip of about 15°, and are overlain conformably by blue 
shales. The junction-beds are one mass of nummulites, closely allied 
to Nummulites complanata and JN. biarritzensis, of all sizes up to 
2 inches in diameter, weathering into a gravel entirely composed of 
these fossils. 
The outcrops of Kocene strata apparently form a belt stretching 
in an easterly-and-westerly direction for about 40 miles, as Viquesnel 
notes similar fossils at Margarice, 3 miles south of Vernitza; and 
Vicomte d’Archiac identifies Nummulites Ramondi and Orbitoides sub- 
media in yellowish compact limestone, subcrystalline, with splintery 
fracture, from Bournar Oren near Examil, on the isthmus between 
the Gulf of Xeros and the Sea of Marmora.’ He also notes 
Nummulites biarritzensis and N. Ramondi in brownish-grey lime- 
stone from Mount Serian, 2 leagues north-east of Kavak, and again 
NV. Ramondi in yellowish-grey compact limestone with waxy fracture 
from Mount St. Elias, near Sterna.’ 
At the last-named locality, the conical summit of the mountain, 
2300 feet above the sea, is a mass of coarse marble dipping 20° south- 
eastward, with seams of calcite weathering into distinct crystals 
about a quarter of an inch along their edges. The eastern and 
1 Op, cit. pp. 824, 466, 467, 2 Tbid. p. 457. 
