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GLACIAL SUCCESSION IN NORWAY.
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general post-glacial upheaval, and as the depression in southern Sweden may be a quite local, peripheric phenomenon attached to the Baltic, I must insist upon the more significant, yet neutral, form subglacial period for the age of the lower beach line.

The inland ice was then, as explained, reduced to a zone (about 50 kilometers broad) across the middle of the eastern valleys. This fact must have a curious consequence in the fact that these valleys must have been dammed up by the ice and filled with lakes whose outlets ran west and north through the gaps in the watershed. These glacial lakes have actually left very distinct marks in the greatest eastern valleys in Norway, Gudbrandsdal and Oesterdal. We not only find in their upper tracts enormous terraces of material brought by the glacier from the south, terraces without any parallel on the other side of the watershed, but we also find here very fine beach lines—seter—partially cut in the rock, corresponding in height with the terraces and with the draining gaps, 620m, 660m respectively—quite like the famous Parallel roads of Lochaber, but very much more extensive. From these ice-dammed subglacial lakes there flowed great rivers across the present watershed filling up with their heavy sediment many of the epiglacial lakes on the northwestern coast, and building great subglacial clay terraces at the level of the lower ancient sea beach.

The erosion of the marginal glaciers has set its mark also in the subglacial time in some inland lakes as Storsjö and Sensjö, in Oesterdalen, Mösvatn and Totak, in Telemarken which have their greatest depth in the upper part and terminal moraines at the present upper end of the lakes.

So far as I can see the subglacial period also prevailed in North America, without receiving yet, however, due attention from glacial students. I cannot here deal with all the raised beaches in the east formed by the sea and by the lakes which naturally can be referred to this period, but I shall use the occasion to point out that the apparently insoluble difficulty in harmonizing archeological and biological facts with the geological data connected with the ancient "Quaternary" lakes in the Great Basin

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