of a Geological Survey of Russia. 419 



that remarkable mass of rock which forms the peninsula of the 

 Volga near Samara, and which, clearly exposed in lofty, vertical 

 cliffs, and charged with myriads of the curious fossils Fusilina, 

 constitutes one of the striking features of Russian geology. 



The carboniferous system is surmounted, to the east of the 

 Volga, by a vast series of beds of marls, schists, limestones, 

 sandstones and conglomerates, to which I propose to give the 

 name of " Permian System," because, although this series re- 

 presents as a whole, the lower new red sandstone (Rohte todte 

 liegende) and the magnesian limestone or Zechstein, yet it can- 

 not be classed exactly (whether by the succession of the strata 

 or their contents) with either of the German or British sub- 

 divisions of this age. Moreover the British lithological term 

 of lower new red sandstone*, is as inapplicable to the great 

 masses of marls, white and yellow limestones, and gray copper 

 grits, as the name of old red sandstone was found to be in re- 

 ference to the schistose black rocks of Devonshire. 



To this " Permian System" we refer the chief deposits of 

 gypsum of Arzamas, of Kazan, and of the rivers Piana, 

 Kama and Oufa, and of the environs of Orenbourg ; we also 

 place in it the saline sources of Solikamsk and Sergiefsk, and 

 the rock salt of Iletsk and other localities in the government 

 of Orenbourg, as well as all the copper mines and the large 

 accumulations of plants and petrified wood, of which you have 

 given a list in the ' Bulletin' of your Society (anno 1840). Of 

 the fossils of this system, some undescribed species of Producti 

 might seem to connect the Permian with the carboniferous 

 aera; and other shells, together with fishes and Saurians, link 

 it on more closely to the period of the Zechstein, whilst its pe- 

 culiar plants appear to constitute a Flora of a type intermediate 

 between the epochs of the new red sandstone or " trias " and 

 the coal-measures. Hence it is that I have ventured to consi- 

 der this series as worthy of being regarded as a " System/' 



The overlying red deposits which occupy a great basin in 

 the governments of Vologda and Nijni Novogorod, have not 

 as yet been found to contain any organic remains except minute 

 Cyprides and badly preserved Modiolce ; but when we take into 

 consideration their thickness, geological position, and mineral 

 characters, we are disposed to think that they may at some fu- 

 ture day be identified with a portion of the " Trias" of German 

 geologists. I am strengthened in this opinion by Count Key- 

 serling's discovering, during our tour at Monte Bogdo, certain 

 fossils which are unknown in other parts of Russia, but which 

 are associated with the Ammonites Bogdoanus already described 

 by Von Buch, and which that distinguished geologist refers to 

 the type of the muschelkalk. 



* See Silurian System p. 54. 

 2 E2 



