The Geographical Journal (Journal of the Royal Geographical Society): Volume X, No. 6 [‎121r] (94/186)

THE MONTHLY RECORD.
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as at 1’ arnace on the flood. Thus there is always in progress a gentle mingling of
the deep waters of the two deep basins through the intermediate shallow basin.
I he rapid surface current of the ebb carries out the excess of fresh water from the
Arran basin, while tne small underflow from the Arran basin passes in water of
higher salinity with the flood. This circulation is liable to be accelerated or
checked by the influence of wind.
The Development of the Peninsula of the Apennines. —In notes on this
subject which Dr. Ih. bischer contributes to the August and September numbers
of Petermanns Mitteilungen, he points out, among other things, that, while north
of Campania transverse breaches in the mountains of the peninsula do not occur
on a great scale, and scarcely affect the regions of the Apennines at all, south of
that province they form a very marked feature. Straits, closed only in geologically
recent times, connected the Campanian gulf with the Adriatic, and the Tyrrhenian
sea with the Ionian, both at the isthmus of Catanzaro, and further south at the
constriction immediately to the north of Aspromonte, while a marginal breach
isolated the heights of Poro on the west, and a longitudinal channel severed Gar-
gano and the Apulian tablelands from the Apennines; so that there existed here,
probably in middle Pliocene times, six islands in place of the continuous stretch of
land reaching to the straits of Messina. Extending his view to neighbouring
countries, Dr. Fischer confirms, from his own observations, the accuracy of the
view of Suess, that the Apennines are continued in the folded mountains on
the north margin of “Little” Africa, and he describes the north-west basin of the
Mediterranean as bordered on the east and south by a series of folded mountains
stretching from Genoa, through Sicily, along North Africa to Melilla, and then
back to Gibraltar and the south coast of Andalusia, on the inner side of which
there is a vast area of sunken land, which he calls the Tyrrhenis, characterized
almost everywhere on the marginal faults adjacent to the mountains by volcanic
activity, and still represented by fragments rising above the surface of the water.
Speaking of the terraces of Calabria and Sicily, he states that recent investigations
have clearly established the fact that, at least in Calabria, a prolonged elevation,
interrupted by periods of repose, and hence indicated by the formation of terraces,
has taken place in quaternary times. This elevation apparently increased in
intensity towards the straits, towards which part the elevation that may almost
everywhere be shown to have taken place in Sicily also seems to have reached its
greatest amount. From the south-west angle of the Sila to the straits, Cortese
has demonstrated the existence of five terraces, all characteristic shore formations,
increasing in height towards the south. In a special note on Gargano and Apulia,
Dr. Fischer points out that recent geological observations tend to establish the
intimate relationship of these tracts to the Apennines, notwithstanding the exist
ence of the Pliocene channel above referred to. The hippuritic limestones of
Gargano are exactly similar to those of the Apennines; and in the Neapolitan
Apennines numerous more or less tabular masses of limestone, not unlike the
tablelands of Apulia and Gargano, have been discovered. The result of the investi
gations hitherto made would seem to be that Gargano and Apulia are portions of
the pre-Miocene Apennines less affected than the central parts of the system by
the folds accompanying the elevation of those mountains, afterwards separated
from the central mass by a series of faults, and behaving as a rigid mass during
the last decisive post-Eocene movements of the Apennine system. Dr. Fischer
makes light of the phytogeographical evidence in favour of a supposed recent land-
connection bringing these parts of Italy into closer relation with the opposite
coasts of the Balkan peninsula than with the Apennine peninsula. Some of the
plants common to the Dalmatian coast and Gargano, but not met with in the rest