The following diagrammatic section shows the general sequence of
the Permian deposits in the north of England, where the series
is extensively developed (fig. 133):--
[Illustration: Fig. 133. GENERALISED SECTION OF THE PERMIAN ROCKS
IN THE NORTH OF ENGLAND.]
The record of the _life_ of the Permian period is but a scanty
one, owing doubtless to the special peculiarities of such of the
deposits of this age with which we are as yet acquainted. Red rocks
are, as a general rule, more or less completely unfossiliferous, and
sediments of this nature are highly characteristic of the Permian.
Similarly, magnesian limestones are rarely as highly charged with
organic remains as is the case with normal calcareous deposits,
especially when they have been subjected to concretionary action,
as is observable to such a marked extent in the Permian limestones.
Nevertheless, much interest is attached to the organic remains,
as marking a kind of transition-period between the Palaeozoic
and Mesozoic epochs.
[Illustration: Fig. 134.--_Walchia piniformis_, from the Permian
of Saxony, a, Branch; b, Twig, (After Gutbier.)]
The _plants_ of the Permian period, as a whole, have a distinctly
Palaeozoic aspect, and are far more nearly allied to those of the
Coal-measures than they are to those of the earlier Secondary
rocks; though the Permian _species_ are mostly distinct from
the Carboniferous, and there are some new genera.
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