Page:A Treatise on Geology, volume 1.djvu/278

 262 tertiary strata should be so distinctly related to the present configuration of the surface of the earth, and so various both as to mineral character and organic contents, though the basins, as we term them, in which they now appear, were parts of one general ocean. In a few instances, however, the tertiary deposits were almost totally formed in vast lakes or inland seas, as in the valley of the Rhine, from Basle to Bingen.

The relation of tertiary deposits to existing seas will appear from the following classification of the European deposits:—

1. Connected by gradual inclinations with the North Sea.

2. Between the Baltic and the Black Sea.

3. Dependent on the English Channel.

4. Bordering the Atlantic.

5. Bordering the Mediterranean.

Besides these are the following secluded tracts:—