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sive (usually some few meters) bed of fluvioglaeial sand, through which 

 the ground moraine, which has a very undulating surface, rises up here and 

 there like islands. The tluvioglaeial sand is covered by a thin (ca. 1 / 2 m.) 

 deposit of stony sand, which I judge from its whole appearance and nature 

 (scattered, unsorted stoncs, contents of tine material in larger quantities than 

 in the undertving sand, the wanting stratification) to be a ground moraine 

 of a thin ice-sheet which has been of short duration. 



As above mentioned, the bogs on the higher land are found in depres- 

 sions, which can be distinctly observed on the surface of the land. Their 

 exact position in the above-mentioned series of deposits has however 

 only been determined with certainty for the bogs on Tuesbol Common and 

 at Skovlyst, which rest directly on moraine clay. For the remaining bogs 

 only sand has been noted as subjacent bed; but whether this sand is fluvio- 

 glaeial sand or whether it is freshwater sand which has heen washed out 

 into the basin in which the bog has been formed, cannot for the present be 

 determined; the last view is however the most probable, as I have found 

 plant remains for example in the sand under the bog in Brorup Station town. 



The bogs nowhere appear open without any cover; the latter is however 

 never moraine clay, but sand of greater or less extent, varying from 1 to 

 5 m. This sand is considered by N. O. Holst (1901) as drift sand, whilst 

 A. Jessen (1905) believes that it is due to a slide, partly also washed or 

 blown out over the peat from the surrounding country. The transport is 

 considered to have mainly occurred during the advance of the inland ice, 

 which came after the formation of the bogs (according to Jessen however 

 the ice did not reach so far to the west), and the great accumulation of snow 

 in winter together with the sudden thawing in spring would form such large 

 quantities of water on the surface of the land, that the upper layers would 

 become sodden and tims ready to slide. 



I am unable however to agree with either of these views. That in these 

 districts the sand has moved almost everywhere in postglacial (and late 

 glacial) times is certainly correct; but the extensive beds of sand with great 

 stones which lie above the interglacial bogs, is not drift sand, but of pleisto- 

 cene age. In the sections above the bogs (specially well developed above 

 the bog of Hollund Sogaard) I have observed quite the same distinction be- 

 tween the stony sand and the stratified fluvio-glacial sand as in sand pits 

 and other sections outside the bogs; further, it seems to me that the above- 

 mentioned, large stones in the sand above the bog on Tuesbol Common and 

 at Lundtofte speak distinctly against the view, that there has been a sliding 

 of the sand or that it has been blown out from the neither high nor steep 

 ridges round the bogs. 



I can therefore only consider the sand above the bogs, which cannot be 

 distinguished from the ordinary stony sand and fluvio-glacial sand, as evidence 

 that the bogs are older than the last glaciation of the group of ridges — 

 even if the iee-sheet has only lain here a relatively short time and had a 

 relatively small thickness. 



It seems to me therefore, that we have here both palaeontological 

 and stratigraphical evidence for the interglacial age of the fossi- 

 liferous beds; their flora and fauna show that they cannot be 

 postglacial, their mode of deposition that they cannot be pregla- 

 cial. Under the supposition that there have been several inter- 

 glacial periods in our country, the general features of the depo- 



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