GEOLOGICAL SOCIETY OF LONDON. 
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the upturned ends of the greywacke. The lowest member of it 
is an old red sandstone conglomerate, consisting of fragments of 
greywacke and felspathic rocks, cemented by a paste which is 
generally arenaceous, sometimes calcareous. It varies much in 
thickness. 
3. Red and greenish white sandstones succeed with soft red ar- 
gillaceous strata. Part of these seem to have been formed in a 
shallow sea, since they exhibit ripple marks, and contain Holop- 
tychius and Dendrodus. Another portion contains few traces of 
fossils, and was probably deposited in deeper water. Some 
curious spindle-shaped concretions and the impressions called 
Kelpie^s feet occur, also traces of fuci. Two localities near 
Preston-Haugh, and one at the foot of the Knock-hill, are all 
in which organic remains have yet been found. 
4. After the deposition of the strata containing the remains of 
the Holoptychius, &c., a subsidence to a considerable extent 
took place, after which a succession of strata of great thickness 
was deposited above them. These rocks seem to have been for- 
med in deeper water than the ichthyolitic beds. They consist of 
red and greenish white sandstones interstratified with beds of a 
softer and more argillaceous character, and of a deep red colour. 
They, seem to contain no organic remains except vegetable im- 
pressions (Alg83?) which occur in abundance in a bed of red 
sandstone perhaps 100 feet above the strata containing the ani- 
mal remains. 
5. Above the soft red and white sandstone are calcareous 
shales, sandstones and cornstones, or impure concretionary lime- 
stones without fossils. The junction of these with the sand- 
stones is not seen, being cut off by faults and trap dykes. 
6. The lower portion of the coal measures succeeds, consisting 
of shales, marls, clays, and sandstones containing ironstone 
bands and gypsum, and abounding in vegetable fossils, consisting 
of Conife7'(Ef Stigmaricej Lepidodendra, and other coal plants. 
This formation is well developed over the greater part of the 
