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following all the sinuosities of a most contorted country, and some- 
times doubled back upon itself for many miles together, may be 
traced by its Kiesel Schiefer and Possidonia schists, and sometimes 
by its black fetid limestones, to the eastern limit of the chain of older 
rocks near Bleiwasche and Stadtberge. 
§ 3. Devonian System.—The authors next describe the rocks im- 
mediately inferior to the carboniferous groups. The mountain lime- 
stone of Cromfort, above-described, rests on dark-coloured shale, but 
the descending section is much obscured by overlying deposit. In 
the long range of the same series, from Elberfeldt to Menden, there 
are many clear transverse sections, exhibiting in greater or less per- 
fection-‘the following descending order—(1.) Immediately under the 
lower limestone shales are many reddish bands, with calcareous con- 
cretions, in which the Possidonia and some of the species of the 
superior groups are still found. (2ndly.) These are succeeded by 
a well-marked range of psammites and coarse flagstone. (3rdly.) 
From beneath the psammites rise a series of shales, and bands of 
psammite of dark colour, with here and there thin courses of inferior 
limestone, in which we find flattened Goniatites, and shells of a 
species different from those of the overlying formations, among which 
especially is noticed the Yerebratula aspera of Schlotheim. These 
are, therefore, considered as forming a part of an inferior system, 
and the first and second groups of the section may be regarded as 
made up of beds of passage between the carboniferous system and 
that which is below it. ‘The sequence here given is compared with 
the highest beds of the Devonian series, immediately under the culm 
measures, and with the yellow sandstones of Ireland described by 
Mr. Griffith. 
3a. Lower Limestone of Westphalia, gc.—This limestone rises 
immediately from below the third group of the preceding section. 
Its range (from the neighbourhood of Ratingen, in the valley of the 
Rhine, to the confines of Hessia) is described in detail. Its changes 
of mineral structure—its separation here and there into two zones— 
its contraction in one place and its great expansion in another—its 
enormous flexures and occasional inversions of position—its re-ap- 
pearance at Warstein and Attendorn, in consequence of such flex- 
ures,—ail these phenomena are noticed in their turn. As a whole, 
it has so great a resemblance to the limestone of South Devon, that 
through large tracts of Westphalia the two could not, by a series of 
land specimens, be distinguished from one another. ‘The fossils of 
this limestone are very abundant, and several sections are given in 
detail, to show their local distribution. Among the most character- 
istie and abundant in these sections the following are enumerated : 
Stromatopora polymorpha, S. concentrica, Favosites ramosa, Favo- 
sites polymorpha, F’. spongites, F'. Gothlandica, Strygocephalus Bur- 
“im, Gypidium, Terebratula aspera, Turritella coronata, T. bilineata. 
(Schlotheim), Buccinum spinosum (Sowerby), &c. &c. From all 
these facts, it is inferred, that this lower limestone of Westphalia isia 
true Devonian limestone, exactly or very nearly on a parallel with 
the great limestone of South Devon. 
