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Part II. Sect. v.§ 2.] PERMIAN. 755 
Lower Sandstone—This subdivision attains its greatest development 
in the vale of the Eden, where it consists of brick-red sandstones, with 
some beds of calcareous conglomerate or breccia, locally known as 
“brockram,’ derived from the waste of the Carboniferous Limestone. 
These red rocks, extending across the Solway into the valleys of the Nith 
and Annan in the south of Scotland, lie unconformably on the Lower 
Silurian rocks, from which their breccias have been derived, but near 
Dumfries some calcareous breccias or “ brockrams” occur. These brec- 
ciated masses have evidently accumulated in small lakes or narrow 
fjords. In the basin of the Nith, and also in Ayrshire, numerous small 
volcanic vents and sheets of porphyrite and tuff are associated with the 
red sandstones, marking a volcanic district of Permian age. The vents 
rise through Coal-measures as well as more ancient rocks. Much 
further south, in Staffordshire, and in the districts of the Clent and 
Abberley Hills, the brecciated conglomerates in the Permian series 
attain a thickness of 400 feet. They have been shown by Ramsay to 
consist in large measure of volcanic rocks, grits, slates, and limestones, 
which can be identified with rocks on the borders of Wales. Some of 
their blocks are three feet in diameter and show distinct striation. These 
Permian drift-beds, according to Ramsay, cannot be distinguished by any 
essential character from modern glacial drifts, and he has no doubt that 
they were ice-borne, and, consequently, that there was a glacial period 
during the accumulation of the Lower Permian deposits of the centre -of 
England. 
Like red rocks in general the Lower Permian beds are almost barren 
of organic remains. Such as occur are indicative chiefly of terrestrial 
surfaces. Plant remains occasionally appear, such as Caulerpites (supposed 
to be of marine growth), Lepidodendron dilatatum, Calamites, Sternbergia, 
and fragments of coniferous wood. The cranium of a labyrinthodont 
(Dasyceps) has been obtained from the Lower Permian rocks at Kenil- 
worth. Footprints referred to members of the same extinct order have 
been observed abundantly on the surfaces of the sandstones of Dumfries- 
shire, and also in the vale of the Eden. 
Magnesian Limestone group.—This subdivision is the chief repository of 
fossils in the Permian system. Its strata are not red, but consist of a 
lower zone of hard brown shale with occasional thin limestone bands 
(Marl Slate) and an upper thick mass of dolomite (Magnesian Limestone). 
The latter is the chief feature in the Permian (Dyas) development of the 
east of England. Corresponding with the Zechstein of Germany, as the 
Mar! Slate does with the Kupferschiefer, it 1s a very variable rock in 
lithological characters, being sometimes dull, earthy, fine-grained, and 
fossiliferous, in other places quite crystalline, and composed of globular, 
reniform, botryoidal, or irregular concretions of crystalline and frequently 
internally radiated dolomite. ‘he Magnesian Limestone runs as a thick 
persistent zone down the east of England. It is represented on the 
Lancashire and Cheshire side by bright red and variegated sandstone 
covered by a thin group of red marls, with numerous thin courses of 
limestone, containing Schizodus, Bakevellia, and other characteristic fossils 
of the Magnesian Limestone. 
The Magnesian Limestone group has yielded about 100 species belong- 
ing to 46 genera of fossils—a singularly poor fauna when contrasted with 
that of the Carboniferous system below. The brachiopods (9 genera, 21 
3 Ga 
