238 LAMPLUGH : SHELLY MORAINE OF THE SEFSTROM GLACIER. 
or other marine detritus showed that in this case w e had to deal 
with the land-spoil of the glacier and not with re-distributed marine 
deposits. 
Though the seaward cliffs of the moraine, so far as I saw them, 
were composed throughout of this red boulder-clay, there must 
have l^een places farther from the sea where grey Carboniferous 
detritus of local origin w as mixed in preponderant quantity with 
the red drift, as the morainic rock- waste on the surface of the ice 
at the southern flank of the glacier appeared to be mainly con- 
stituted of such local material. In traversing some moraine- 
covered ice on this flank, I noticed that amid the sheets of angular 
grey Carboniferous rubble there were streaky patches, here and 
there, of dirty red ice, carrving some well-glaciated boulders of 
the ancient rocks. It was clear that at these places the deeper 
moraine was somehow being brought up to the surface of the 
glacier. Fortunately, the moraine-charged ice near the southern 
edge of the glacier was notched by a deeply-cut stream-guUy, 
accessible from the shore. The section in the walls of this gully 
near its mouth exhibited moraine-laden ice bent into sharp 
upward curves and sigmoidal contortions (see PI. XXXVII.) ; 
and in one place a belt of ice sweeping boldl}^ upward was charged 
with red mud and scratched stones. Avhile above and below 
the ice was charged with the dull grey local debris. The section, 
in fact, beautifully illustrated the conditions, described by 
Garw^ood and Gregory in other Spitsbergen localities, whereby 
the lower layers near the end of a glacier are deflected upward 
along shear planes and brought to the surface.^ 
If it came about that this glacier received no further acces- 
sion, so that it became stagnant and now melted down without 
movement, it w ould leave as a residue, in the part we saw . tw^o 
very different kinds of drift : the lower, a red clay Avith far- 
transported stones : the upper, a grey rubbly clay with a pre- 
ponderance of local stones, mostly unglaciated : and the two 
would show, in some places, complicated inter-digitation and 
banding. 
In our British drifts it has often been deduced that a difference 
of composition in successive beds of boulder-clay implies separate 
periods of glaciation ; but the e\idence of the Von Post inoraines 
show s that the deduction is unsafe. 
I Op. cit. Quart. Jouni. Geol. Soc, Vol. LIV. (1898), p. 203 ei seq. 
