On the Cretaceous Flora of Eiassian Sakhalin. 



.extensive area than was formerly believed. The lower part of 

 the Tertiary rocks, just as in Japanese Sakhalin and in Hokkaido, 

 is lying conformably upon the Cretaceous, with two thick conglo- 

 merates at the boundary, which are intercalated with thin layers 

 of coal-bearing shales. The relation between the Lower and Upper 

 Tertiary coal -bearing rocks have not been well observed, but the 

 latter rest disconcordantly upon the Cretaceous, being itself only 

 slightly disturbed. 



The Lower Tertiary or the Dui Series is chiefly coal-bearing 

 and consists of sandstones, some conglomerates and shales with 

 coals, which are partly of a good coking quality. This Tertiary 

 includes two different horizons of shales with marine shells which 

 have not yet been determined, besides there are some basalt sheets 

 with tuffs associated with them, and mainly overlying the marine 

 strata of the Series. 



The Upper or Mgach Series consists chiefly of rather loose 

 sandstones and shales with some seams of long-flamed coal in the 

 lower part, which are covered by loose hght-grey clayish sand- 

 stones and clays with marine shells. 



The Dui Series is found on the sea coast only between Cape 

 Rogatyi and Cape de la Jonquière, being partly disturbed and 

 pierced or replaced by basaltic effusives. A little to the south of 

 a line drawn between Khoinju and Krasny Yar, the Lower Ter- 

 tiary rises up just to the ridge of the Coastal Kange. 



The other places of the coast are occupied only by the Creta- 

 ceous and by coal-bearing and marine divisions of the Younger 

 Tertiary. 



The valley of the river Dui, (officially called now " Alexan- 

 drofka "), represents a deep graben, showing a compressed synchnal 

 of the coal-bearing and marine Tertiaries. 



The young marine beds appear also on the seashore, from the 



