ö Art. 8. — A. Kryslitofovicli : 



north of the mouth of the Dai to the mouth of the Little Sertunai. 

 There are calcareouä concretions with Pecten propatulus Cone., 

 Cardium decoratum Grew., C. coosense Dall, C. ccdvartensium. Glehn, 

 C. meeklanum Gabb, Thracia condoni Dall, determined by N. 

 TiKHONovicH and P. Polevoi.^^ 



The underlying coal-bearing strata appear only a little inland, 

 as in the Vladimirsky and Mgachinsky coal-mines, which belong 

 to the eastern wing of the coastal anticlinal. More to the north, 

 just at the village Mgach,^^ the Tertiary beds, mostly coal-bearing, 

 are found on the sea coast, unconformably overlying the Creta- 

 ceous and partly covering it, by simple slipping down along minute 

 faultings in the cliff in an imperfectly consolidated state, and pro- 

 bably partly by more complicated movements. To the north of the 

 village Machi, the high scarp of sea shore consists of nearly horizontal 

 marine deposits, replaced by the Cretaceous only on the space 

 from Cape Tangi to Capo Khoi. There are some indications of 

 the probable occurrence of the Tertiary, developed far inland on 

 the river Tangi. 



The general stratigraphy of the Tertiary is not yet clearly es- 

 tablished, on account of the want of detailed determination of fossils. 



Cretaceous. The Cretaceous deposits play an important part 

 in the structure of the western part of Russian Sakhalin in a far 

 greater degree than was formerly assumed. The whole Coastal Range 

 between the river Dui (Alexandrofka) and the Gulf of Tartary is 

 Cretaceous, partly covered by Tertiary rocks, whose lower division 

 is conformable but the upper unconformable with the Cretaceous. 

 The ridge of the Western Range is also Cretaceous, and the rocks 

 appear like steep ribs, projecting out of younger deposits of the 



1) TiKHONovicH and Polevoi (1915), p. 40. 



2) In official writings, the place is called Machi, and the mine Mgach ; the latter being 

 the more exact transUteration of the Gyliak original. 



