26 On the Phcenician Tin Trade in Cornwall, by R. Edmonds. 
ing any vegetable remains, but studded with land-shells so perfect 
that they must have been buried in situ (on the very spots where 
their inhabitants had been pasturing or hybernating) by gradual 
accumulations of sand, which neither covered the herbage nor 
checked its growth. These shells, now seen in situ, are the only 
existing evidence that turf ever grew in those strata of light sand. 
To this process of accumulation by the agency of the winds 
there is a remarkable exception in the long sand-bank between 
Penzance and Marazion, the herbage of the highest parts of which 
appears to have been once completely covered by gravel and small 
pebbles, deposited directly by the sea. In a section of the highest 
part of this bank, near Marazion bridge, in 1846, I observed an 
extensive layer of small rounded pebbles and gravel three feet 
below the green surface, and not less than ten or fifteen feet above 
the level of high water ; whilst in the subjacent sand, deposited 
by the winds alone, numerous perfect land-shells (the Helix vir- 
gata and Bulimus acutus) were embedded throughout a depth of 
four or five feet beneath the pebbles. This was at the eastern ex- 
tremity of the bank, and within a few yards of the spot where my 
nephew and myself afterwards found the two fragments of the 
bronze furnace above described. Near its western extremity 1 saw, 
in 185], a precisely similar stratum, and at the same depth from 
the surface, in the deepest of the cuttings made for the railw'ay, 
close on the eastern side of a line from Gulval church to the pole 
on the Cressars Rock.* Here, too, perfect land-shells were em- 
bedded throughout a depth of four or five feet beneath the pebbles. 
This stratum is now faced up by a stone wall. The distance 
between the two spots is a mile and a half. In each case, the 
layer was about an inch thick, and extended between ten and 
twelve yards in diameter, over a part of the bank more elevated 
* This most elevated western part of the sand-hank, or rather the western slope 
of it, is remarkahle also for being the only known place in Cornwall where the Cyno- 
don Daclijlon grows, which, in France, is one of the most common grasses found by 
the wayside. 
