T. BELT ON THE STEPPES OE SOUTHERN RUSSIA. 855 



bergs that carried the northern blocks southward. That water 

 covered the Yaldai Hills, which are over 1100 feet in height, and rose 

 on the flanks of the Carpathians to over 1200 feet above the present 

 sea-level, and was therefore sufficient also for the tiistribution of the 

 diluvial clay and the loess of the Danube. There is no occasion to 

 look for any other cause ; but the questions still to be determined 

 are, whether the water was that of the sea, or, if not, how it was 

 dammed up to such great heights and in such immense volume. Sir 

 Roderick Murchison was of opinion that nearly the whole of Russia 

 had been submerged beneath the sea. And, indeed, it seems most 

 reasonable to conclude, when we take into consideration that some of 

 the boulders have been carried more than 700 miles from their 

 parent rocks, and that the diluvial beds cover nearly the whole 

 country, and are absolutely independent of the lines of drainage, 

 that there must have been a sea-like expanse of water; and in 

 Murchison's time there was no other way known by which such a 

 submergence could be produced, excepting by the sinking of the 

 land below the level of the ocean. 



Yet the objections that may be urged against a marine submerg- 

 ence are very strong. We have seen that from the time of the 

 isolation of the Sarmatic sea there is evidence of successive freshen- 

 ings of its water until, at the time of the deposition of the Paladbia- 

 beds, it appears to have become perfectly fresh, at least in the 

 western part of the basin. The surface of the lake was then 

 lowered ; and when, after a long interval, during which the Miocene 

 beds were greatly denuded, the water again began to rise and to 

 regain some of its former extended limits, we find, from the fauna 

 contained in the fluviatile beds, that it was still quite fresh. Then 

 succeeds the diluvial clay, in the bottom part of which a few fresh- 

 water shells still occur, whilst in the upper portion only land shells 

 are found. Surely if the sea had again covered this area, as it did 

 in early Miocene times, it would have left some memorials of its 

 presence. We are precluded from imagining that they may have 

 existed, but have been destroyed, by the perfect preservation of the 

 freshwater and land shells. 



Dr. Dawson, who is the principal advocate of a marine sub- 

 mergence of the northern parts of the continents of America and 

 Europe in the Glacial period, has fully perceived the importance of 

 the absence of sea- shells from most of the areas that he supposes to 

 have been beneath the sea, and has offered some reasons to account 

 for it. The freshening of the sea by the entrance of large rivers, 

 or by the melting of ice, may, he thinks, have prevented marine 

 animals from existing. I do not know of any evidence showing 

 that the estuaries of large rivers are not suitable for the abundant 

 sustenance of animal life. Prof. jSTordenskjold has lately shown 

 that even the Kara Sea, within the Arctic circle, and freshened by 

 the immense volume of water brought down by the Obi and Yenissei, 

 is rich in mollusks, crinoids, crustaceans, and other forms of animal 

 life*; and with regard to the melting of ice, there are mol- 



* Nature, vol. xv. p. 124. 



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