On the Cretaceous Flora of Eassian Sakhalin. 11" 



exceptional luxuriance of flora, consisting of ferns, cy cades, conifers 

 and dicotyledons, and found to be equivalent to the Atane Bed of 

 Greenland, and the Dakota, Earitan and Magothy of America, all 

 of which essentially correspond to the Cenomanian, but partly to 

 the Turonian, of Europe. The fauna is entirely wanting, but the 

 coiTesponding series in Hokkaido is that with Mammites, Pectiin- 

 cidus, Thetis, Trigonia and Lytoceras. 



The deposits of this series are developed on the sea coast, 

 from the Mgach coal mine down to the Gulf of Khoi, however 

 with some interruptions, as mentioned before. They are overlain 

 and in places completely covered by Tertiary strata. Another re- 

 gion of the same series is found on the httoral slope of the West- 

 ern Eange near the Pilenga Pass. 



The Orokkian and Gyliakian Series are not actually observed 

 lying one upon the another, and therefore it is not yet possible to 

 draw a sharp boundary line between them. Probably the upper- 

 most part of the beds exposed at Tangi may represent the con- 

 tinental equivalent of the marine beds of the Orokkian. 



The type fossils of the Gyliakian are Nilssonia serotina, Pro- 

 tophyllocladus suhintegrifolius and Aralia Polevoii n. sp. 



III. The Ainu an Seeies. 



Having established the undoubtable presence in Sakhalin of a 

 fossil horizon other than formerly believed, that is the Gyliakian, 

 I ventured to proceed to find one still older. As such I have now 

 to consider the coal-bearing beds in the region of the " Duisko- 

 Nevelsky Coal mine " of Eeikson to the north-east-east of Alexan- 

 drofsk, in the upper ^ coarse of tlie rivulet Polovinka. Polevoi 

 expressed as his opinion, that the abnormal SW dip here marks 

 the existence of an older horizon not yet observed elsewhere. 

 These beds are made up of light-gray sandstones and dark shales 



