174 DK. C. T. TBECHMANN OX IXTEK GLACIAL [vol. lxXV„ 



Avanting in the underlying earlier deposits with which this paper 

 deals. 



A few Avords in recapitulation of matter already published 1 are 

 necessary, in explanation of the peculiar features and mode of 

 occurrence of the bed of Scandina\ 7 ian Drift which is exposed on 

 the Durham coast. Up to the year 1914, Avhen I investigated and 

 described this bed, ScandinaA T ian boulders had never been traced 

 with certainty in situ in Great Britain north of Yorkshire or 

 north of the River Tees. Their occurrence had been certainly 

 from time to time suggested, but they had not been satisfactorily 

 distinguished from the ballast-carried Swedish and Baltic rocks- 

 that occur plentifully scattered on the beach on parts of the coast,, 

 especially in the neighbourhood of the great shipping centres. 



The main drifts are not dealt Avith in this paper, except to be 

 mentioned in the section Avhere the possibility of Interglacial 

 episodes is discussed, and in the attempted representation of the 

 sequence of Glacial events in the district. 



I must express my great indebtedness to the following experts, 

 for the assistance which they have kindly afforded to me in 

 identifying the organic remains : — Mrs. E. M. Beid, Mr. H. X. 

 Dixon,' Mr. A. S. Kennard, Mr. B. B. Woodward, Dr. C. W. 

 Andrews, F.R.S., and Mr. M. A. C. Hinton. 



II. Description of the Bed of L(ess. 



The Scandinavian Drift of the Durham coast is represented by a 

 bed of material which is preserved in a small, Preglacial, A T alley- 

 like depression eroded in the Magnesian Limestone. At the bottom 

 of this old valley occurs a fissure of unknown depth filled with 

 the same material. The stony and shell}' clay filling the fissure 

 and the bottom of the valley is sometimes Avell exposed on the 

 foreshore between tide-marks, where it passes out to sea. A small 

 Postglacial ravine (called Warren-House Grill) has been super- 

 imposed on the site of the old Preglacial A r alley, and cuts down 

 through the overlying main Cheviot Drift and partly also into the 

 underlying Scandinavian Drift. 



In a former paper dealing with this deposit I gave a diagram- 

 matic sketch of the section, and therein described and indicated 

 the position of various Norwegian boulders that occur in situ 

 in the cliff, or lie AA 7 ashed out and exposed on the shore. In 

 describing the section I also made the remark that in parts, but 

 especially towards its southern limit, the upper portion of this 

 drift consists of a bed of pale-brown material full of rounded 

 concretions, that this bed reaches a thickness of 6 feet or more, 

 and is almost deA'oid of stones, though it contains occasional layers 

 of coarse sand. 



The idea that this pale-brown material with concretions might 

 in reality be a bed of the true loess did not occur to my mind 



1 C. T. Trechraann, ' The Scandinavian Drift of the Durham Coast. &c/ 

 Q. J. G. S. vol. lxxi (1915) pp. 53-82. 



