NATURAL HISTORY. 
likely the case) the colouring oxides of the red sand 
formation had penetrated this ; it probably does not 
prevail to any great depth in the solid strata, and 
the texture of the marble where those markings 
occur, is usually more open and unequal than the 
rest. In one or two of the Bickington Quarries, 
megnesia forms a component part of this rock; and 
the mefalliferous variety that sets under water is 
also there met with in beds of 42 or 18 inches in 
thickness. 
Fossil remains occur, though somewhat sparing 
ly, in this formation—they all, (at least as far as our 
observation extends,) belong to the radiated type of 
animals—cermoideze—corallines—madrapores — ser- 
tularie, &c., more or less perfectly preserved. The 
finest impressions are usually procured from beach- 
worn pebbies on the contiguous coast, which have 
probably been detached from the upper and basset 
ends, and locse portions of the adjoining rocks—but 
they occasionally occur, forming the principal por- 
tion of the solid strata. 
This is the case at Coombe-Fishacre in the parish 
of Ipplepen; this rock, the basset end of which pro- 
trudes at a considerable angle through the red sand 
stone, and dips to the eastward, from the upper bed 
to the depth of between forty and fifty feet, (which 
is as low as it has yet been opened) and for the 
widih of several yards, has the whole of its strata 
crowded with Poiypiferous fossils; some of the 
upper beds which are of a very fine and compact 
texture, appear to consist almost wholly of commi- 
