240 LAMPLUGH : SHELLY MORAINE OF THE SEFSTROM GLACIER. 
(1) There is j)i'oof of a former spread of glaciation over 
practically the whole of Spitsbergen ; yet, on the extensive tracts 
of land now bare, there is seldom any conspicuous evidence of this 
event, its traces on the country above present sea -level having 
been reduced by later erosion to remnants difficult of recognition. 
On the A\hole, there is much more drift in an equivalent area of 
the British Islands than is now ^4sible in Spitsbergen. 
(2) Under arctic conditions, stratified rocks similar to those 
covering large areas of our o\mi country are disintegrated to a state 
which Mould favour the production of boulder-clay in quantity 
when the areas were invaded by moving ice. Material of this 
kind is seen to be readily caught up and transported b}^ glaciers, 
and is discharged in huge masses at or near their ends. 
(3) The moraines at and around the ends of some of the 
Spitsbergen glaciers bear a close resemblance in composition and 
structure to some of our British boulder-clays, this being particu- 
larly striking in a terminal moraine of the Sefstrom Glacier and 
in the lateral moraines of the Von Post Glacier. The red clay 
of these moraines is heaped up in ridges and mounds higher than 
neighbouring unglaciated low ground and terminates abruptly 
upon it. The local absence of fluvio-glacial outwash \\as very 
noticeable at the Sefstrom terminal moraine on Cora Island. This 
recalls the conditions on the eastern slope of the Yorkshire Wolds, 
where the red boulder-clay ends off irregularly and indefinitely 
upon the rising ground of bare chalk. 
(4) The ]3resence of vast numbers of shells, mostly unbroken, 
in the terminal moraine of the Sefstrom Glacier after it had crossed 
an arm of the sea shows how readily marine material can be 
hoisted up from the sea -floor and transported by an advancing 
sheet of land-ice. It illustrates the manner in which our shelly 
drifts have been spread by the ice-sheets of the Glacial period 
over the land surrounding our sea -basins. The admixture of 
certain shells not now li\dng in Spitsbergen waters adds to the 
analogy. 
(5) The sudden advance of the ice on Cora Island seems to 
have caused no interruption of the previous conditions on the 
ground not reached by the glacier ; which shows that the influx 
of land-ice need not greatly interfere with the state of adjacent 
land. In this latitude the flora and fauna inhabiting the land 
