422 STEVENSON— INTERRELATIONS OF FOSSIL FUELS. 



Carboniferous deposits seem to be wanting in the region east 

 from Lake Baikal. 



Russia in Europe. 



Murchison^° believed the Carboniferous System of northern and 

 central Russia to be equivalent to the Mountain Limestone and un- 

 derlying deposits of Great Britain, while, on the western slope of the 

 Urals, he recognized the Millstone Grit and Permian. In the Valdai 

 Hills, Province of Novgorod, the Lower Carboniferous consists of, 

 ascending, 



Lower Limestone, with Productus gigantea, associated with 

 sands and some coal beds ; Moscow Limestone with Spirifer mos- 

 quensis; it has no coal in northern and central Russia, but there are 

 seams in the southern Steppes ; Upper Limestone, with Fusulina 

 cylindrical containing coal only in the southern Steppes. 



The sands at base of the Lower Limestone have many pyritized 

 plants, among them Stigmaria ficoides; bituminous shales associated 

 with the sands contain coal. Those on the Pritchka River are 40 

 feet thick and contain 4 coal seams in the upper portion. The coal 

 is extremely imperfect and is from 10 inches to 4 feet thick. Hel- 

 mersen had described this as Moorkohle; it is impure, pyritous, 

 slightly consolidated and is inferior to some Tertiary coals mined in 

 portions of Germany. The cover is largely loose sands and varie- 

 gated marls. 



Nikitin^^ states that the lignite occurs in the Toula District near 

 the Volga. The coal group, at same horizon as in the Valdai Hills, 

 consists of alternating clays and sandstones with more or less con- 

 siderable seams of coal. He thinks it strange that this material, in 

 spite of its great age, has chemical and physical character so closely 

 allied to that of lignite. Boghead, rich in oil, is present at several 

 horizons. At one locality, several thin coals were seen at the base 

 of the Lower Carboniferous, but they have insignificant lateral 

 extent. 



20 R. I. Murchison, " Geology of Russia in Europe and the Ural Moun- 

 tains," London, 1845, Vol. I., pp. 69-71, 78, 126. 



21 S. Nikitin, " De Moskau a Koursk," Guide des Excursions, XIV., St. 

 Petersburg, 1897, pp. 4-7. 



