PREFACE. 
The Permien Rocks of Northumberland and Durham con¬ 
sist, in a descending scale,—of (a) the crystalline and marly 
beds of Sunderland,— (b) the shelly and compact limestone of 
Humbleton, Pallion, and Garmundsway,— (c) the marl slate 
of Ferry Hill, Whitley, and Cullercoats,—and, (d) the lower 
new red-sandstone of Westoe, Claxheugh, and other places. 
Contemporaneous deposits occur at various parts in Germany, 
where they are termed, following the same order, ( a ) Stink- 
stein (including the Rauchwacke), (b) Zechstein, (c) Kupfer- 
scheifer, and (d) Rothe todt-liegendes : and, in the ancient 
kingdom of Permia, on the western-side of the Ural moun¬ 
tains, and in Petchora, bordering the Arctic sea, deposits of 
the same age are extensively developed. These deposits, 
together with the more recent red-sandstone of Cumberland, 
and the vale of Cleveland,—and their equivalent, the Yosgian 
grit of South Europe, constitute the Permien system of Sir 
Roderick I. Murchison, which is the uppermost divison of 
the primary or protozoic class of formations, and the next, as 
an overlying group, to the coal measures of this district. 
Considering the position of the Permien Rocks in the great 
series of formations,—that they were deposited at the close 
of the primary period, and whilst the vegetable and animal 
kingdoms were undergoing most extensive changes,—it is 
