2 PEOP. T. G. BONNEY AND REV. E. HILL ON THE [Feb. I9OI, 



different from those in the Jasmund district. This was the case, 

 though they were not exactly what we had been led to anticipate. 



In looking for papers on E-iigen we unfortunately missed a small 

 monograph by Dr. Eudolf Credner ('Riigen: Eine Insel-Studie,' 

 1893),^ which would have been very useful as a clear statement of 

 one view and as containing a list of the literature after 1886. He 

 considers that in the Arkona and Jasmund areas (but not universally) 

 the 'Diluvium' is naturally separable into a lower member consisting 

 of two greyish-blue boulder-clays with an intervening bedded sand ; 

 and an upper one, of boulder-clays, gravels, and sands, which is 

 imconformable with the other.' He regards the boulder-clays as true 

 ground-moraines ; the sands and gravels as produced from these by 

 denudation. The dislocations to which he attributes the peculiar 

 association of the Chalk and the Lower Drift were produced after 

 the deposition of the latter, but prior to that of the Fpper Drift. 

 In this interval the older one was considerably denuded, which 

 explains its occurrence at the present time only in sheltered places. 

 He maintains that the Chalk has been shattered into a series of 

 blocks which have been thrust one against the other, and bent down 

 irregularly and in many directions : the Diluvium being wedged in 

 among them. As proofs of these movements, he instances the irre- 

 gular distribution of the Drift-masses, which, for example, are small 

 and narrow from Sassnitz to the Kollicker Bach, broaden out near 

 the Monchsteig, and between Stubbenkammer and Lohme occupy 

 nearly the whole coast, occurring in like manner near Arkona. 

 Again, in inland quarries the Chalk is often replaced by Drift. The 

 throw of these dislocations measures from some inches to well over 

 900 feet. Often one block merely sinks against the other without 

 disturbance of bedding, though the latter is also found. In his 

 opinion as many as eleven or twelve such blocks occur between 

 Gakower Ufer and KoUicker Ort. In all cases these dislocations 

 affect onty the lower member of the Drift — the two boulder-clays 

 and the intervening sand. 



II. The Coast neae Waenemunde. 



^ The Drift near Warnemiinde has been described by Johnstrup 

 and Geinitz,^ and again very recently by the latter in a small geolo- 

 gical guidebook for Mecklenburg.^ This contains three photographic 



' See also ' Forschungen zur Deutschen Landes- u. Volkskunde ' vol. vii, pt. v, 



p. 377. 



2 He states that the total thickness of this Drift varies considerably : in the 

 cliffs of Granitz it is from 30 to 40 metres (98-4 to 131'2 feet), on Hiddensoe 

 70 metres (229'6 feet), in well-sinkings it ranges from 20 to 60 metres (65*6 to 

 196"8 feet), and at Quoltitz reaches 96 metres (314-9 feet). 



3 'Beitrag zur Geologic Meeklenburgs ' pts. vi & vii (1884-85). [This work 

 was not in the Society's Library when we wrote, but a copy has now been 

 procured. Pt. vi contains a map of the distribution of the Drifts ; pt. vii a 

 ijauorama of the cliffs, in which, however, the sea appears to have made changes 

 since 1885.] 



* ' Geologischer Fiihrer durch Mecklenburg ' Berlin, 1899. 



