AND NORTHUMBERLAND COAL MEASURES. 233 
which have not yet been satisfactorily determined. At the other 
collieries where we have had opportunities of examining the 
stratum it is certainly not near so fossiliferous in fish-remains 
as it is at Newsham; and from it also decreasing in thickness 
as we recede from the latter point, it would almost appear as if 
it did not extend its area much beyond its already ascertained 
limits. But however this may be, we feel confident that there 
must be other localities in the coal-field where these fossils occur 
in comparative abundance. We are, indeed, already aware of 
other localities where they do occur, at horizons both above and 
below that of the Low Main. 
Certain of these, we hope ultimately to work to some profit: 
but what we more especially look forward to is the discovery of 
other localities where the fossils are preserved in a more satisfac- 
tory condition than they have yet occurred to us. For it may 
be observed that those we propose to describe are nearly all 
in a fragmentary state. Detached teeth or detached mandibular 
and maxillary bones with teeth, other cranio-facial bones and 
plates, bones belonging to the vertebral column and fins, scales, 
fin-spines and smaller dermal spines are, with one or two ex- 
ceptions, the fossils we have hitherto found. Occasionally an 
irregular patch of scales and bones occurs which appears to 
represent all the parts of a fish; but we have only met with 
two specimens whose integrity has been so well preserved as to 
indicate the original contour of the individual when alive. The 
remains of many of the species—more particularly of the Plac- 
oideans—we, of course, cannot expect to find much more entire 
than they have already occurred; but others belonging to the 
Ganoidei we certainly do expect to meet with in new localities 
as beautifully preserved and entire individuals, like the Permian 
fish in the Marl slate and Upper Limestone. 
The fossils which we have selected for notice in the present 
paper belong to species that are new to this coal-field. And it 
may be observed that we have been assisted by Sir Philip de 
Grey Egerton in the determination of them. 
