Yol. 57.] DRIFTS OF THE BALTIC COAST OF GERMANY. 7 



that subterranean denudation of the latter rock would be locally 

 80 intensified as to produce these down-drops in the Drifts ; but if 

 pre-existent valleys in the Chalk had been filled up with frozen 

 snow, prior to the deposit of these alternating strata, or if the lower 

 part of the Drift had enclosed tabular berglike masses of ice, which 

 afterwards melted away, such a structure might be produced.^ Of 

 the two hypotheses, we view the latter with the less favour, but the 

 former also has its own difficulties. We do not, however, see our 

 way to suggesting anything better. 



III. Arkona. 



The headland of Arkona, above the northern end of Riigen, 

 may be described in general terms as an insular mass of Chalk 

 rising about 200 feet above sea-level, and situated at one corner of 

 a slightly lower plateau of Drifts.^ But on closer examination we 

 find that it also is capped by Drift, though of a dififerent colour and 

 composition. This is often from 3 to 5 yards thick ; but at one place, 

 where the coast is projecting towards the east, it apparently reaches 

 a much greater thickness, for the Chalk-cliff below seems to be only 

 30 or 40 feet high.^ It is a light-coloured clayey material, containing 

 numerous flints with some Scandinavian pebbles or boulders, not 

 without a resemblance to the ' whitish boulder-clay ' which occurs, 

 among other places, near the Waldhalle.^ In the cliffs facing east- 

 ward, the Chalk can be seen for a space overlain by the ordinary 

 Drift. Its surface at first seems to sink irregularly, though somewhat 

 rapidlj" southward, perhaps, even to below the sea-level ; but the 

 slipped Drift and grassgrown slopes make any precise statement 

 impossible. In about 150 yards, however, the Chalk certainly 

 rises into a kind of ridge, the top of which is not much below the 

 edge of the cliff. After this, so far as we could see, it finally dis- 

 appears, and the cliffs or slopes are formed of Drift. This bears a 

 general resemblance to the boulder-clays of Jasmund, and reminded 

 us in its general aspect of the masses seen last year ufear Gohren. 

 In one or two places it was sandy, but whether a tripartite division 

 exists here seemed to us more than doubtful. We were unable to 

 examine the corresponding section on the northern face of the 

 headland, but carefully studied the singular ' inlier ' of Drift in the 

 Chalk (seen in the crag near the buildings of the lighthouse) which 

 has been described by Prof. F. Johnstrup.^ His diagram had suggested 



^ To this view, we infer that Prof. Geinitz, on the whole, inclines. 



- It was once a stronghold of the Eugii ; their earthwork, sometimes over 

 30 feet high, still remains crossing the headland. 



3 Possibly the other Drift may come in below, but we had not time to attempt 

 a minute examination of this part, if indeed it is accessible, and had to content 

 ourselves with what we could see from the deck of the steamer, 



* Dr. Credner appears to place both in the ' Ober Diluvium,' Forsch. z. 

 Deutsch. Landes- u. Volkskunde, vol, vii (1893) p. 448. Certainly they appear 

 to be unconformable with the Drifts below, assigned to the 'Unter Diluvium.' 



' Zeitschr. d. Deutsch. Greol. Gresellsch. vol. xxvi (1874) p. 572. More briefly 

 also by Dr. E,. Credner, Porsch. z. Deutsch. Landes- u. Volkskunde, vol. vii 

 (1893) p. 448. 



