- 15 = 
to. cover portions of it and extend into it in places Such an ir- 
regular overlapping and interfingering of deposits is Aoroad or the 
relations between a moraine and an outwash plain that are built si- 
multaneously.e 
The story of the activity of these lobes as they drew back still 
farther to the north and west must te deferred until the quadrangles 
adjacent to those covered by the writers have been mappede 
The area of the Cape .east of the quadrangles that “have been 
mapped in detail is underlain in part ry. deposits continuous with 
those mentioned above. The Mashpee pitted plain extends into the 
Cotuit quadrangle, and the Sandwich moraine stretches eastward along 
the north shore of the Capes NE. Chute's recent study (2) substan- 
tiates the conclusions of earlier workers that anothér large pitted 
plain extends southwestward on the ‘southeastern end of the Cape and 
spreads toward. the Mashpee pitted plain. The eastern arm of the Cape 
from Chatham to Provincetown. may be in part an interlobate moraine 
| formed between the ‘Cape Cod ‘Bay lobe and the Massachusetts Fay lobe, 
| tut the complexities of its geology require careful study “before we 
can outline in any detail the story of Pleistocene conditions in 
that areae 
Wind-seculptured Stones (Ventifacts) 
| During both. the advance and the recession of the Wisconsin ice 
over the Cape Cod region strong winds blew down across its irregular 
surface and whirled up clouds of sand and silt on the outwash. plains 
and the exposed seafloor in front of the glacier. Sandstorms must 
have been frequent, and a current of wind- driven, sand must have been 
| moving close to the land surface almost constantly. Blocks and boul- 
| ders and even smaller stones that lay in the path of this sand-blast 
were worn and polished. Smooth, almost flat surfaces were tevelled 
across rounded rocks. (Fige 4a)e When these stones were dislodged 
and rolled into new positions, other parts of them were likewise 
bevelled. Some of the rounded cobbles became pyramid-shaped and 
sharply angular where one wind-cut facet intersected anothere ‘(Pige 
4b). Even granite and quartzite pebbles; which are normally as hard 
as or harder than steel, were shaped by this incessant abrasion. 
Many of the wind-scoured stones have irregular pits and grooves or 
furrows where the sand stream etched out their less resistant partse 
uPig. 4c,¢e,f) 
Some stones lay exposed to such action for a long time, and 
they bear marked evidences of the wind-cutting; others were quickly 
covered or protected by falling into the lee of larger stones or by 
being shifted out of the wind-blast, and they show only the begin- 
nings of modification by sand-hlastinge Some of these stones, or 
course, never moved out of position before they were buried by sand 
or ty later till or outwashe They show wind-sculpturing, therefore, 
on but one side. Some were picked up after they had teen cut and 
were moved to a different location by streams of meltwater or by the 
advancing ice itself. Consequently, they now lie embedded in till 
or deep within the layers of outwash gravel. Turing this second 
