north DEVON. 
163 
of a palm, fPoacites Cocoina^) and frag¬ 
ments of the trees called Sternbergia and 
Sigillaria, attest the former existence of 
flourishing groves, separated fiom each 
other by vast intervals of time, during 
which layer after layer of thick hard sedi¬ 
ment accumulated on the buried soil The 
carboniferous matter in this locality is usu¬ 
ally but a thin film, sometimes a distinct 
seam, and at one or two places large enough 
to tempt the adventurer to extract it; but 
the whole forms a profitless representation 
of the productive coal measures of other 
and more favoured spots. Alike in the 
coarse slaty character of their composition, 
and in the tokens of flexure and disturbance, 
it is extremely difficult, without the aid of 
fossils, to separate the culm-bearing strata 
from the older rocks. 
We have to speak of the Devonian and 
Silurian systems, which will exhaust the 
catalogue of fossiliferous deposits. All be¬ 
neath are either sedimentary rocks so alter¬ 
ed as to obliterate all traces of organic life, 
or crystalline masses, which have evidently 
suffered more than a '"sea-change,” and 
bear proofs of former fusion. 
