44 SLATE FOSSILS. 
many like creatures. Some of these fossils I have 
had represented for their better identification by the 
collector, but, many through obscurity of character 
would defy the efforts of the graphic art in exhibit- 
ing their actual appearance. But, so far from the 
fossils of the slate being limited to these kinds of 
animals, we discover the remains of conchifers, and 
perhaps of fish in it, and, should doubt exist on this 
important point—important, if only identifying the 
slate rock as of equal consequence in its contents, 
with the limestone,—it may be here mentioned, that 
slate in other parts contains fish and shells. The 
Tintagel and Snowdon slates for instance, contain 
the latter fossils. (see De la Beche’s Manual.) 
It is usual, to find fossils much accumulated to-. 
gether in certain spots, as is the case also in lime 
and sandstone, and this rule even extends to each 
kind of fossil, to a limited extent. Thus, I have 
found a kind of zoophyte very numerous within a 
small compass of about a foot square, and occurring 
but rarely elsewhere ; in general also, each fossil 
seems to have its own special locality, whether 
numerous or sparing in quantity. Greywacké slate 
may be known from roofing slate by its fossils, and 
roofing slate, from ordinary clay-slate by the same 
means, though less decidedly. 
Excluding the consideration of indistinct fossils 
before spoken of, encrinetal remains are most com- 
mon, and there seem to be several species, all 
different from those in limestone. Remains of a 
zoophyte, or something similar in growth to a coral- 
line, are perhaps next in the order of frequency. 
Turbinolias, of which there are apparently three, 
or more kinds, rank next; one sort is plentiful 
in a hard slate on the shore at Boveysand. The 
calamopores in slate, seem almost always to occur 
at the line of junction with lime, and are probably 
of the same species as occurs in the latter rock so 
