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very destructive to organic remains, so that we can form but a 
limited idea of the life which existed, nor can we tell to what 
extent coal forming vegetation has been destroyed, and the loss 
thereby sustained ; but in the pebbly conglomerates of the 
Upper Pennant specimens of wood are to be found wonderfully 
well preserved. 
In the Pennant are a few seams of coal which constitute the 
middle series. They are chiefly used for smiths’ work and house 
coals, but the uncertainty of their thickness is remarkable. 
This may in part perhaps, depend upon the amount of chemical 
decomposition to which the seam has been subject, during and 
after submergence; the chemical character of the roof is 
very changeable and this would influence the decomposition, 
causing it to be unequal. 
The Flora of the Pennant so far as can be ascertained up to 
the present time, consists of Newropteris flexuosa, heterophylla. 
Alethopteris Bucklandi, Pecopteris hemiteloides, Cistii, cequalis, 
cyatheites, Miltoni ; Sigillaria Candollei, organium, laevigata, 
tessellata ; Lepidodendron aculeatum, Veltheimiana, rimoswm, Stern- 
bergii ; Calamites radiatus, canneformis ; Ulodendron majus, 
Trigonocarpum and Cordaites. 
The Pennant was brought to a close by the sinking of the 
land, on which was deposited argillaceous beds of some 150ft. 
thick, coloured by iron in the ferric state. These form a sort 
of lithological passage between the Pennant and the base of 
local upper series of coal measures, but not a vestige of plant 
life has been obtained in these beds. 
The lapse of time which extended over the deposition of these 
beds must have been considerable, as when land again appeared 
and vegetation grew, new genera and species had come into 
existence. The seams of the Upper Series are house and gas 
coals especially noted for the high illuminating power of the gas. 
The lowest seam of coal is the Great Vein, at Parkfield Colliery, 
it is only divided from the Holly Bush seam above by about a 
foot of Duns, but to the south the distance between the two 
increases, and ground comes in characterised by the occurrence 
of Neuropteris (Huneuropteris) cordata in great numbers. 
