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their carbon from the imbedded remains ? These are all 
highly interesting questions, but they cannot be solved 
unless our collection of specimens embraces a contribution 
from all the localities where the remnants of fishes exist. 
For these remains the iron-stones too should be carefully 
searched, for it Is often the case that a tooth or copro- 
lite forms the nucleus of the iron-stone. The most 
perfect specimens of fishes are in the Leeds Museum; the 
locality of one is uncertain, but the other is stated to have 
been procured from Low Moor, and I have myself seen 
pretty good specimens which have been obtained there ; 
and to Low Moor I think we may look for a supply for 
the Wakefield Museum. Some strata at Middletpn con- 
tain large numbers of teeth and scales, but no specimen 
of a perfect fish has been found. The same strata are 
found at various other places. I think similar specimens 
may exist there. The Flockton collieries, Rothwell Haigh, 
the roof of the Stanley shale coal, and many other places are 
rich in their remains ; in fact, I may lay it down as a 
general rule, that they may be found in greater or less abun- 
dance over nearly the whole of the Yorkshire coal seams. 
Conchology — 
A series of fossil shells from all parts of the district — in 
order to determine not only their species, but to understand 
under what condition they have been deposited, or whether 
they have lived where they are now found. Some shells it is 
well known extend in a continuous layer for nearly a mile, 
but do they not extend even further? others are found 
imbedded in shale one by one in a peculiar manner, the 
hinge always being the lowest ; others again are found in 
large masses of ironstone in the shape of flat or compressed 
balls ; do we find the same species of shell in all places under 
precisely the same circumstances ? and lastly, do we in the 
same stratum find shells and fish associated with entomostraca 
