of the Island qfCerigo and its Dependencies, 267 



which have fallen from the precipices, by which it is on all sides 

 surrounded. Two others still remain, called Stavrolo and St 

 Georgio, which can only be approached by boats in north-east 

 winds. 



Sketch of Formations. 



Nearly the whole of the northern district of Cerigo consists 

 of primitive slaty rocks, while the higher parts of the middle 

 and southern districts are chiefly transition, with their valleys 

 more or less covered by tertiary and alluvial deposits. 



Primitive District,~^li consists chiefly of mica-slate, which 

 passes into clay-slate on the south-west of the district. Among 

 the varieties of mica-slate, the common and undulated were 

 most frequently met with ; but the fine slaty was noticed in 

 the neighbourhood of the clay-slate, and the talcose in several 

 parts near the north end of the island : the common variety 

 contains felspar in several places. The clay-slate is of a blackish- 

 grey, and sometimes of a bluish-grey colour. 



Associated with the mica-slates and clay-slates, the following 

 minerals were noticed occurring either in beds or veins. Lime- 

 stone. — Of it we observed several beds, but the most exten- 

 sive is about half a mile to the south-east of the village of Po- 

 tamo, where it is sometimes of a white and at other times of 

 a grey colour, pretty highly crystallized, but full of flaws. 

 Serpentine. — It occurs in small beds, of a green colour, on the 

 north-east coast, where it is occasionally mixed with limestone, 

 forming what is called Verde Antico. Quartz. — It occurs of va- 

 rious colours, in beds and veins in different parts of the district ; 

 but it is most abundant at the north end. Near Orthohthas there 

 are veins of a richly coloured pale blue variety. Iron-ores, — 

 Several kinds were noticed, of which the most common were spe- 

 cular iron-ore, compact red iron-ore, and compact brown iron-ore, 

 occurring sometimes in the form of veins, as the specular iron on 

 the acclivity of mica-slate opposite Santa Pelagia, and the red 

 iron-ore near Potamo village, in the clay-slate ; the brown iron- 

 ore occurs in beds in clay-slate in a lateral valley a little to the 

 south of the village of Potamo. 



Stratification* — The direction of the strata was everywhere 



