Nr. 6] 



KVARTÆR-STUDIER I TRONDHJEMSFELTET 



221 





Subatlantisk 



Recent peat 



Littorina-iiden 



Subboreal 



Upper forestian 



Atlantisk 



Upper peat bog 

 Second arctic bed 

 Lower peat bog 



Ancylus-tiden 



Boreal 



Lower forestian 





First arctic bed 



(cfr. Geol. Forn. Forh. Stockholm, B. 30, 1908, pag. 263). At 

 her Sernander sammenstiller »Lower forestian« med »Boreal«- 

 og »A/7Cf//us«-tid, er kun, hvad Geikie allerede tidligere hadde 

 gjort (Smithsonian Report 1898 (1900), pag. 345). Den efterføl- 

 gende tid skildres af Geikie paa følgende maate: — »Eventually, 

 however, submergence ensued — — — it is notable that the 

 character of the marine fauna which at this stage lived off the 

 coasts of Scandinavia and Britain is indicative of more genial 

 conditions than now obtain. The climate, however, gradually 

 became colder, the vertical and horizonlal range of the forests 

 was restricted, and snow fields again appeared among the higher 

 mountains of our Islands. In Scotland glaciers here and there 

 came down to the sea, and dropped their moraines upon the 

 beaches there forming; the large majority, however, terminated 

 inland« (L. c. pag. 345). Og videre fortsætter han: » Later cli- 

 matic oscillations followed, but on a decidedly reduced scale. 

 The effect of these was, naturally enough, most marked in north- 

 western Europe, decreasing gradually southward, and doubtless 

 eventually fading away in the lower latitudes of the continent« 

 (L. c. pag. 346). »The local glaciers of the British Mountains, 

 some of which, as I have said, actually entered the sea, at last 

 began to retreat. The climate became more genial, and so once 

 more favored the growth of forests, which in many places began 

 to overspread the now dry peat bogs, beneath which the trees 

 of the earlier forest epoch lay entombed. Eventually, however, 

 colder and more humid conditions returned, and small glaciers 

 appeared in a few places among the loftiest heights of the Scot- 

 tish Highlands — — — The forests now, as before, began to 

 decay in many places, and the bog moss and its allies again 

 extended in all directions, and so, eventually, a second forest 

 bed became entombed in growing peat. It is needless to say 

 that the evidence of these later changes is not restricted to Scot- 

 land. The bogs of the two sister countries, and of the corre- 



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