70 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [NoV. 18, 



another perfect specimen on a former occasion, said to be from 

 Koumi. 



The deposits in the Kastrovalla valley have a dip to the south of 

 a few degrees, so that in the lower part of the valley the lignite is 

 again seen, but the whole of the lacustrine beds are overlaid by 

 beds of brownish sandy marl and gravel, forming low hills and 

 ridges from 50 to 200 feet in height, extending over a district of 

 three or four square miles. 



These gravelly beds contain no fossils, and in every respect corre- 

 spond in description and position with those in the island of Samos 

 before noticed. 



Section 4. District of Kastrovalla. 



3 2 



3. Gravel. 

 2. Lacustrine beds. 

 1. Secondary limestone. 



s. Serpentine. 

 t. Trap. 



Section No. 4 is on a line nearly north and south through this 

 district, showing the position of the gravelly beds, and also of trap 

 ejected through the lacustrine deposits. 



I next examined the two shores of the south channel between 

 Euboea and Greece, on both sides of which I found evidences of the 

 ancient freshwater lake having existed there also, viz. at the Bay of 

 Stura in Euboea, where the freshwater deposits and gravel repose 

 upon mica schists ; but they are not so extensive or so well-deve- 

 loped as in the district to the south of Oropo, on the confines of 

 Bceotia and Attica. 



Sections. Section near Markopoulo. 



Secondary limestone. Lacustrine gravel. 



At B. is a band of lignite. 



Section No. 5 crosses this district near the village of Markopoulo, 

 in a line due west from the channel. A narrow strip about seven 

 miles long and two miles wide lies parallel to the shore, which is com- 

 posed of deposits closely resembling those at Koumi, even to the pre- 

 sence of the lignite ; they are however here inclined at a greater angle, 

 viz. 20°, and repose on or surround the secondary limestone, that 

 rises into a higher chain of mountains behind, forming Mounts 

 Parnes and Citheron, which separate Attica from Bceotia. 



The gravelly beds also occur here precisely under the circum- 

 stances and in the same condition as at Koumi, and unconformable to 



