nation of marine-formed beds with fresh-water or land formations. 

 For every considerable oscillation of the beach-lines there is a 

 corresponding geological stage. In these stages there is a certain 

 number of alternations. Upon studying the literature on the 

 Tertiary basins of Europe, I have, in that way, formed a combined 

 profile which, in respect of the alternation of strata, is certainly 

 not yet everywhere filled up, but which starts from the com- 

 mencement of the Tertiary period and extends until our own 

 day, and I will now pass on to describe it. The manner in 

 which profiles can be compared with the curve and the correct- 

 ness of the hypotheses be tested, is as follows. Each arc of 

 the curve corresponds to one oscillation of the sea. For higher 

 latitudes it is assumed that the beach line oscillates up and 

 down with the curve. Such an oscillation I term a geological 

 stage. Each arc must therefore have its corresponding oscillation 

 or stage and in each stage there must be as many alternations 

 of strata as there are periods of precession in the corresponding 

 arc. When the eccentricity between two or more arcs only falls 

 slightly, neighbouring arcs form mountains, as it were, with two 

 to three small peaks. We therefore obtain „ stages" with sev- 

 eral more oscillations and several more alternations of strata 

 than usual. . We shall see instances of that in what follows. 

 We may draw a line, intersecting the curve of eccentricity, denot- 

 ing the margin between salt and fresh- water formations. That line 

 may be almost or quite level. Whether it is to be drawn high or low, 

 depends on how elevated above the sea the place was, where the beds 

 were formed when the formation of the beds took place. The higher 

 it lay the higher must the line be drawn. The place may have been 

 situated so high that it was never covered by the sea. In that 

 case the line lies higher than the entire curve, and all the beds 

 are fresh- water or land formations. Or the place may have been 

 situated so low that it never reached above the surface of the 

 sea. In that last case the line lies lower than the entire curve, 

 and all the beds are marine formations. Or the line may in- 

 tersect the curve In that case the marine beds alternate with 

 land and fresh-water ones. The first-named correspond to the arcs 



