GEOLOGICAL OBSERVATIONS 



as on an oyster-bed. Now the limestone is absolutely barren, no plant can 

 find nourishment in its cracks, no sign of animal life was to be discovered, and 

 one finds oneself wondering why the inland-ice, which from both sides sends 

 its glaciers right to the edge, does not fling down its masses of ice, filling up 

 the clough. 



When these layers were formed there must have been variable conditions at 

 the bottom of the sea. The orthoceratites did not live here whilst the red 

 limestone was deposited, and only in occasional places did favourable conditions 

 for animal life exist ; but this animal life was then very rich, though it soon 

 died out again and was covered by a stratum void of fossils. 



The upper layers of this limestone, however, point to somewhat different 

 conditions. Between the brachiopods occasional corals are found, becoming 

 increasingly numerous upwards at the same time as the large, thick-shelled 

 brachiopods become rarer ; ultimately one sees no more of them, the rock 

 becomes bluish-grey, and the corals dominate. 



The succeeding layers are remarkable for their great wealth of animal life. 

 They are especially easy to find in Washington Land. Now one stands on 

 almost a coral reef, now the many-armed crinoidea put their stamp on the stones, 

 and in between the branches of the corals lie remains of innumerable other 

 organisms. The Crustacea are represented by trilobites, by octopus, by ortho- 

 ceratites ; further, there are brachiopods, mussels, snails, bryozoa, and fungi. 

 The corals are present in many varieties ; some are cup-formed, others are 

 sausage-shaped or ball-shaped, others, again, are flat or look like a plate. 



But the period of the corals also comes to an end. The bluish-grey layers 

 with the beautiful branches of coral suddenly stop, and are succeeded by black 

 strata of schist, in which at the first glance no animal remains can be seen ; 

 these layers look very much like slate-stone. But if one examines them 

 closely one will find some peculiar shapes which look as if they had been 

 traced on the slate with varnish. Now they are small, saw-toothed sticks, 

 now they are rolled up and have long radiate beams on the outer side ; they 

 are the so-called graptolites, an animal group long ago extinct, which does not 

 appear to have any near kindred amongst now existing animal forms. 



The black schists are very thin ; towards the top they become richer in 

 lime and at the same time the trilobites again appear ; but they are chiefly of 

 forms different to those in the coral limestone, and the same holds good for 

 the brachiopods and the orthoceratites. They are mainly small, but of many 

 varieties, and it is as if animal life for the last time flares up before it dis- 

 appears. If one follows the succession of layers upwards, the slaty lime- 

 stone rather abruptly becomes mixed with sand, and then merges into pure 

 coarse sandstone without fossils. 



This sandstone crumbles easily, wherefore landscapes consisting of this 

 stone appear in the shape of low plains with rounded forms. A whole series of 

 low districts are therefore to be found to the north of the large fossiliferous 

 plateaux right from Hall Basin and almost to Peary Land. 



With this the North Greenlandic series is finished. All the fossiliferous 

 strata belong to the Silurian Period. The coarse sandstone shows that the 

 sea again becomes shallow, and one gets the explanation of this if one turns 

 towards the north, where the plains are bordered by an enormous mountain 

 chain. 



All the layers deposited in the sea, right from the red sandstone, the dark 

 brown and the reddish-grey limestone, to the coral lime, the black schist, the 



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