PASSAGE mOM.SECONrfARY TO PRIMARY ROCKS. 385 
PKIMARY OR PALJ50Z0IC SERIES. 
CHAPTER XXII. 
PEEMIAN OR MAGISTESIAI^^ LIMESTONE GROUP. 
Line of Separation between Mesozoic and Palaeozoic Rocks.—Distinctness 
of Triassic and Permian Fossils.—Term Permian.—Thickness of calcare¬ 
ous and sedimentary Rocks in North of England.—Upper, Middle, and 
Lower Permian. — Marine Shells and Corals of the English Magnesian 
Limestone.—Reptiles and Fish of Permian Marl-slate.—Foot-prints of 
Reptiles.—Angular Breccias in Lower Permian.—Permian Rocks of the 
Continent.—Zechstein and Rothliegendes of Thuringia.—Permian Flora. 
—Its generic Affinity to the Carboniferous. 
In pursuing our examination of the strata in descending 
order, we have next to pass from the base of the Secondary 
or Mesozoic to the uppermost or newest of the Primary or 
Palaeozoic formations. As this point has been selected as a 
line of demarkation for one of the three great divisions of the 
fossiliferous series, the student might naturally expect that 
by aid of lithological and palaeontological characters he 
would be able to recognize without difficulty a distinct 
break between the newer and older group. But so Tar is 
this from being the case in Great Britain, that nowhere have 
geologists found more difficulty in drawing a line of separa¬ 
tion than between The Secondary and Primary series. The 
obscurity has arisen from the great resemblance in color and 
mineral character of the Triassic and Permian red marls and 
sandstones, and the scarcity and often total absence in them 
of oi’ganic remains. The thickness of the strata belonging 
to each groups amounts in some places to several thousand 
feet; and by dint of a careful examination of their geologi¬ 
cal position, and of those fossil, animal, and vegetable forms 
which are occasionally met with in some members of each 
series, it has at length been made clear that the older or 
Permian rocks are more connected with the Primary or Pa¬ 
laeozoic than with the Secondary or Mesozoic strata already 
described. 
The term Permian has been proposed for this group by 
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