HAWELL : A PEAT DEPOSIT AT STOKESLEY. 
51 
regard the Stokesley bed as more likely to have been contem- 
poraneous with the shell deposit at Kildale than with the 
overlying peat. Both were at this epoch localities of arrested 
drainage, but at the Kildale tarn the forest growth was less 
dense, and the sun's rays got through with some degree of 
freedom, and decaying vegetable matter was transferred to the 
atmosphere, whilst molluscs lived happily and died peacefully, 
and their shells fell to the bottom of the water, forming in time 
a thick deposit. At Stokesley, on the other hand, the forest- 
growth was probably dense, and the vegetable matter accumulated 
freely there, while the circumstances were unsuited to the life 
of molluscs. 
It is practically certain that this part of Yorkshire has 
undergone some amount of elevation since the Stokesley peat was 
deposited. This elevation, which probably amounted to 20 ft. or 
30 ft., would give origin to an improved drainage system for 
the locality. There was, however, perhaps first a temporary sub- 
sidence during which the fine clay was laid down over the peat. 
