292 
LAMPLUGH : GLACIAL SECTIONS NEAR BRIDLINGTON. 
curious how persistent all over England and Scotland is this rubble 
of the local rock at the base of the drift series. The reason of the 
striking distinction which frequently occurs between it and the over- 
lying glacial beds, especially with regard to the quantity of extraneous 
material they contain, is not very easy to explain when they are both 
regarded as moraine pr of oiide, and we have in this comparison one of 
the many, yet unexplained problems of glacial geology. 
Again, on both sides of Flamborough Head, at Sewerby, and at 
Speeton we find the relics of marine beds below the Basement Clay 
and its associated chalk-rubble, that appear to have accumulated 
before there was any boulder-clay existing in the neighbourhood, 
(the few drift pebbles in the old beach at Sewerby I regard as the 
product of drifting ice), and these prove an open sea, a shore-line, and 
a land-surf\ice tenanted by numerous large mammals, such as the 
elephant, rhinoceros, hippopotamus, bison, etc., at a period not long 
anterior to the formation of the Basement Clay, the relative level of 
land and sea not being very different from what we hnd at present. 
It may be urged that we could hardly exi)ect that the first deposit 
of the age would be a bed containing proof of such extreme glacial 
conditions as the Basement Clay. But I believe that a careful study 
of the physical geography of the region will dispose of this objection, 
by showing that the area was incapable of initiating for itself a 
system of glaciation, and consequently remained practically unglaci- 
ated until the arrival upon the coast of the great mass which had 
crept on slowly from the north and east. However, this is a point which 
I reserve for further discussion upon a future occasion. 
If we can indeed satisfactorily establish that the Basement Clay 
and its associated beds have been the first deposit of the glacial period 
in East Yorkshire, we shall have materially simplified the study of 
that period in Eastern England. We could then accept the Speeton 
Estuarine Shell-bed and the Sewerby Buried Cliff-beds as pre- or early 
fflacial (sub-glacial), and compare them with beds found at similar 
levels and under somewhat similar conditions below the drifts of 
Norfolk, while in the Basement Clayiitself we should recognize the 
equivalent of the Cromer Till. But more work must be done before 
we can place any such correlation on a really satisfactory basis, and it 
