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decke and Sehwerte, and of yellowish and light-coloured sandstones 
and grits, with thin seams of coal and impressions of plants ; and the 
strata are underlaid by dark gray micaceous slates and thin-bedded 
hard sandstones, of great thickness, marked by many obscure impres- 
sions of small plants. The lowest member of this series contains much 
dark pyritous shale (Alaun Schiefer of the Germans), and reposes on 
the upper calcareous zone of Westphalia (mountain limestone). 
Several sections are described which confirm this order of su- 
perposition. ‘The authors then state that this lower division of the 
coal-field is greatly expanded towards the north-east ; that it is litho- 
logically almost identical with the great eulm-field of Devon, and 
resemble it also in its numerous impressions of small plants. It is 
the Flotzlehrer Sandstein of the German geologists, and had been 
regarded by them as the highest member of the graywacke series ; 
but in the recently published map of Von Dechen, it is placed on 
‘the parallel of the millstone grit of England. 
§ 2. Carboniferous limestone of Westphalia (Berg-Kalk), Kiesel 
Schiefer, and bituminous limestone, §e.— Theauthors next describe the 
limestone which commences at Cromford, near Ratingen, and ranges 
east-north-east to Velbert. Thence deflecting to the valley of Re- 
grath, north of Tonnesheide, it is cut off, and does not form a con- 
tinuous band (as represented in all the German maps), with a lower 
limestone, which commences a few miles further south, and ranges 
through Metman to Elberfeldt. Near Cromford the limestone is 
thick-bedded, and in its structure and fossils resembles the great 
scar-limestone of England. For proofs the authors give several de- 
tailed sections, and quote published lists of fossils. In its range to 
the east it becomes more cherty, and abounds in casts of the stems 
of Encrinites, so as to resemble the screw-stones of Derbyshire. At 
several places (e.g. Isenbugel, Velbert, &c.) the connexion of the 
limestone with the upper series is well exposed. ‘The upper beds of 
limestone pass into dark flat-bedded flinty slate, which is overlaid by 
psammite and shale, with thin courses of flinty slate, and these dip 
under the lower members of the coal-field. Again, there is at Vel- 
bert a clear proof that the limestones, screw-stones, and flinty slate, 
dip under the alum-slates of the neighbourhood. 
Following the strike of the county still further to the east, the 
limestone range loses its mineral character; but a large group of 
strata (dipping under the alum-slates above-mentioned, and resting 
on dark shales, like those which form the base of the limestone) oc- 
cupy the exact place of the carboniferous limestone in the transverse 
sections. ‘The group is characterized by dark flinty slate (Avesel 
Schiefer) and dark and often fetid thin-bedded limestone, and so 
closely resembles the culm-limestone series of Devonshire, that the 
description of one formation might almost serve for the other. Like 
the culm-limestone, it also contains many Goniatites and Pessidoniz ; 
and among the latter, the Possidonia Becheri of Devon. It wants, 
however, the numerous species of mountain limestone fossils of the 
beds above-noticed, a fact which the authors explain by a reference 
toa change in all the physical conditions of the deposit. This group, 
