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number. The affinities of the fossils of this and the 
preceding system are more in conformity with those of 
the Oolitic, but have some forms which are peculiar. A 
rather shallow sea or salt lake, whether inland or other- 
wise, largely charged with saline matter and red peroxides 
and an arid climate, are characteristic conditions of the 
Triassic system generally. 
The Permian rocks in this county have given us little 
evidence of the life of the period, though remarkable as 
affording the head and jaws of a Labyrinthodont reptile, 
in the Museum, besides some shells and plants, which are 
in a very imperfect condition. In the north of England 
it is rich in mollusks, corals, and fish; therefore it would 
seem that the conditions in this area were not favourable 
to the existence of a marine fauna, and we must look 
elsewhere for it. This system is very closely allied to 
the Carboniferous with which many of the fossils agree 
generically. 
The absence of the marine mountain limestone in this 
county, and the unfossiliferous condition of the millstone 
grit leave the overlying coal measures as the only portion 
of the great carboniferous system to afford any insight 
into its geological history. Here, as elsewhere, abundance 
of peculiar plants, mostly succulent, and all endogenous, 
prove the vast amount of vegetable life which then pre- 
vailed, with abundance of carbon and a moist tropical 
heat, such as we find in some portions of the globe at the 
present day. For the most part these plants grew on or 
near the spot, in swampy tracts favourable to their 
growth; but in some cases they may perhaps have been 
carried down by streams into the sea, marine and estuarine 
shells, numerous fishes, some reptiles, and crustacea being 
in many places associated with them. On the whole, the 
conditions were apparently more favourable to the growth 
