The universal geography : earth and its inhabitants

ARCTIC RUSSIA.3Urunning north-west and south-east parallel with those scored on the rocks ofFinland and Olonetz.The uplands separating the Volga and arctic hasins still hear the traces of thefrozen masses by which they were formerly covered. As they gradually melted,these glaciers formed the fresh-water lakes now filling all the hollows of theland, and which formerly rose 60 or 70 feet above their present level. ThisFig. 182.Northern Urals.Scale 1 :3,600, 0CO.Eof Gregion seems never to have been invaded by the sea, so that during recent epochsno communication can have existed between the Baltic and the Arctic Ocean, aswas at one time supposed. The seas were, however, indirectly connected by a labyrinthof lakes and rivers sufficiently to account for the exchange of fishes andCrustacea which has taken place between the two marine basins. In this way theinland waters may have also been colonised by the Phoca vitulina, a species of seal