The distinction between the Mammaliferous Crag of Norwich and the Red
Crag of Suffolk is purely palæontological, no case of superposition
having yet been discovered, and they are now generally considered as
contemporaneous. Two Proboscidians abundant during the Crag period were
the _Mastodon Arvernensis_ and the _Elephas meridionalis_. In the Red
Crag the Mastodon is stated by the Rev. John Gunn to be more abundant
than the Elephant, while in the Norwich beds their proportions are
nearly equal.
At or near the base of the Red Crag there is a remarkable accumulation,
varying in thickness from a few inches to two feet, of bones, teeth, and
phosphatic nodules (called coprolites), which are worked for making
superphosphate of lime for agricultural manure.
The foreign equivalents of the older Pliocene are found in the
_sub-Apennine strata_. These rocks are sufficiently remarkable in the
county of Suffolk, where they consist of a series of marine beds of
quartzose sand, coloured red by ferruginous matter.
At the foot of the Apennine chain, which forms the backbone, as it
were, of Italy, throwing out many spurs, the formations on either side,
and on both sides of the Adriatic, are Tertiary strata; they form in
many cases, low hills lying between the Apennines of Secondary formation
and the sea, the strata generally being a light-brown or bluish marl
covered with yellow calcareous sand and gravel, with some fossil shells,
which, according to Brocchi, are found all over Italy. But this wide
range includes some older Tertiary formations, as in the strata of the
Superga near Turin, which are Miocene.
The _Antwerp_ Crag, which is of the same age with the Red and Coralline
Crag of Suffolk, forms great accumulations upon divers points of Europe:
at Antwerp in Belgium, at Carentan and Perpignan, and, we believe, in
the basin of the Rhône, in France. The thickest deposits of this rock
consist of clay and sand, alternating with marl and arenaceous
limestone. These constitute the sub-Apennine hills, alluded to above as
extending on both slopes of the Apennines. This deposit occupies the
Upper Val d’Arno, above Florence. Its presence is recognised over a
great part of Australia. Finally, the seven hills of Rome are composed,
in part, of marine Tertiary rocks belonging to the Pliocene period.
In PLATE XXV. an ideal landscape of the Pliocene period is given under
European latitudes. In the background of the picture, a mountain,
recently thrown up, reminds us that the period was one of frequent
convulsions, in which the land was disturbed and upheaved, and mountains
and mountain-ranges made their appearance. The vegetation is nearly
identical with the present. We see assembled in the foreground the more
important animals of the period--the fossil species, as well as those
which have survived to the present time.
Public-domain text, read in full here on John Shaqi.
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