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ing the Lower Molasse of Switzerland as belonging to the Miocene
rather than to the latter part of the Eocene period. There are,
indeed, so many types among the fossils both specific and generic
which have a wide range through the whole of the Molasse, that
a unity of character is thereby stamped on the whole flora, in
spite of the contrast between the plants of the uppermost and
lowest formations, or between QEningen and Monod. The proofs
of a warmer climate and the excess of arborescent over herba-
ceous plants and of evergreen trees over deciduous species, are
characters common to the whole flora, but which are intensified
as we descend to the inferior deposits.

Nearly all the plants at Monod arc contained in three layers
of marl separated by two of soft sandstone. The thickness of
the marls is ten feet, and vegetable matter predominates so
much in some layers as to form an imperfect lignite. One bed
is filled with large leaves of a species of fig (Ficus populina), and
of a hornbeam (Carpinus grandis), the strength of the wind
having probably been great when they were blown into the lake ;
whereas another contiguous layer contains almost exclusively
smaller leaves, indicating, apparently, a diminished strength in
the wind. Some of the upper beds at Monod abound in leaves
of Proteacese, Cyperaceae, and ferns, while in some of the lower

L'2



220



LOWER MOLASSE OF SWITZERLAND. [CH. xv.




Sdbal major, linger sp. Vevay, Lower



ones Sequoia, Cinnamomum, and Sparganium are common. In
one bed of sandstone the trunk of a large palm tree was found
Fig. lg4t unaccompanied by other fossils,

and near Vevay, in the same
series or Lower Miocene strata,
the leaves of a fan-palm of the
genus Sabal (fig. 154), a genus
now proper to North America,
were obtained.

Among other genera of the
same class is a Flabellaria occur-
ring near Lausanne, and a mag-
nificent Phcenicites allied to the
date-palm. When these plants
flourished the climate must
have been much hotter than now.

Miocene. '(Heer, Pi. 4L) The Alps were no doubt much

lower, and the palms now found fossil in strata elevated 2,000
feet above the sea grew nearly at the sea-level, as is demon-
strated by the brackish- water character of some of the beds into
which they were carried by winds or rivers from the adjoining
coast.

In the same plant-bearing deposits of the Lower Molasse
in Switzerland leaves have been found which have been ascribed
to the order Proteacese already spoken of as well represented in
the GEningen beds (see p. 203). The Proteas and other plants
of this family now nourish at the Cape of Good Hope ; while the
Banksias, and a set of genera distinct from those of Africa, grow
most luxuriantly in the southern and temperate parts of Aus-
tralia. They were probably inhabitants, says Heer, of dry hilly
ground ; and the stiff leathery character of their leaves must have
been favourable to their preservation, allowing them to float on a
river for great distances without being injured and then to sink,
when water-logged, to the bottom. It has been objected that
the fruit of the Proteacese is of so tough and enduring a texture
that it ought to have been more commonly met with ; but in the
first place we must not forget the numerous cones found in the
Eocene strata of Sheppey, which all admit to be proteaceous and
to belong to at least two species (see p. 248). Secondly,, besides
the fruit of Hakea before mentioned (p. 204), Heer found asso-
ciated with fossil leaves, having the exact form and nervation of
Banksia, fruit precisely such as may have come from a cone of
that plant, and lately he has received another similar fruit
from the Lower Miocene strata of Lucerne. They may have
fallen out of a decayed cone in the same way as often happens



en. xv.] LOWER MOLASSE OF SWITZERLAND.



221



to the seeds of the spruce fir, Pinus abies, found scattered
over the ground in our woods. It is a known fact that



Fig. 155.



Fig. 156.





a. Fruit of a fossil Banksia.
6. Leaf of Banksia Deekiana.



Sequoia Lang&dorfii. Ad. Brong, \ natnra
size. Rivaz, near Lausanne. (Heer, PI. 21,
fig. 4.) Upper and Lower Miocene and
Lower Pliocene, Yal d'Arno.



a. Branch with leaves.



6. Young cone.



among the living Proteaceae the cones are very firmly at-
tached to the branches, so that the seeds drop out without the
cone itself falling to the ground ; and this may perhaps be the

Fig. 158.



Fig. 157.




Lastma stiriaca, Ting. (Heer's Flora, PI. 143,

fig. 8.)

Natural size. Lower and Upper Miocene.
Switzerland.

a. Specimen from Monod, showing the position of
the sori on the middle of the tertiary nerves.

6. More common appearance, where the sori re-
main and the nerves are obliterated.




Cinnamomum Rossmassleri, Heer.
Daphnogene cinnamomifolia, Un-
ger. Upper and Lower Miocene
Switzerland and Germany.



reason why, in some instances in which fossil seeds have been
found, no traces of the cone have been observed,



222 ARCTIC MIOCENE FLOE A. [en. xv.

Among the Coniferse the Sequoia (fig. 156) is common at
Rivaz, and is one of the most universal plants in the Lowest
Miocene of Switzerland, while it also characterises the Miocene
Brown Coals of Germany and certain beds of the Val d'Arno,
which I have called Older Pliocene, p. 189.

Among the ferns met with in profusion at Monod is the
Lastrxa stiriaca, linger, which has a wide range in the Miocene
period from strata of the age of (Eningen to the lowest part of
the Swiss molasse. In some specimens, as shown in figure 157,
the fructification is distinctly seen.

Among the laurels several species of Cinnamomum are very
conspicuous. Besides C. polymorphum, before figured, p. 201,
another species also ranges from the Lower to the Upper
Molasse of Switzerland, and is very characteristic of different
deposits of Brown Coal in Germany. It has been called Cinna-
momuin Rossmdssleri by Heer (see fig. 158). The leaves are
easily recognised as having two side veins, which run up un-
interruptedly to their point.

American character of tne flora. If we consider not merely
the number of species but those plants which constitute the
mass of the Lower Miocene vegetation, we find the European
part of the fossil flora very much less prominent than in the
(Eningen beds, while the foreground is occupied by American
forms, by evergreen oaks, maples, poplars, planes, Liquidanibar,
Robinia, Sequoia, Taxodium, and ternate-leaved pines. There
is also a much greater fusion of the characters now belonging to
distinct botanical provinces than in the Upper Miocene flora,
and we shall find this fusion still more strikingly exemplified as
we go back to the antecedent Eocene and Cretaceous periods.

Professor Heer has advocated the doctrine, first advanced by
Unger to explain the large number of American genera in the
Miocene flora of Europe, that the present basin of the Atlantic
was occupied by land over which the Miocene flora could pass
freely. But other able botanists have- shown that it is far more
probable that the American plants came from the east and not
from the west, and, instead of reaching Europe by the shortest
route over an imaginary Atlantis, migrated in an opposite direct
tion crossing the whole of Asia.

Arctic Miocene Flora. But when we indulge in speculations
as to the geographical origin of the Miocene plants of Central
Europe, we must take into account the discoveries recently made
of a rich terrestrial flora having flourished in the Arctic regions
in the Miocene period from which many species may have mi-
grated from a common centre so as to reach the present conti-
nents of Europe, Asia, and America. Professor Heer has



en. xv.] ARCTIC MIOCENE FLORA. 223

examined the various collections of fossil plants that have been
obtained in N. Greenland (lat. 70), Iceland, Spitzbergen, and
other parts of the Arctic regions, and has determined that they
are of Miocene age and indicate a temperate climate. 1 Includ-
ing the collections recently brought from Greenland by Mr.
Whymper, the Arctic Miocene flora now comprises 194 species,
and that of Greenland 137 species, of which 46, or exactly one-
third, are identical with plants found in the Miocene beds of
Central Europe. Considerably more than half the number are
trees, which is the more remarkable since at the present day
trees do not exist in any part of Greenland even 10 farther
south.

More than 30 species of Coniferse have been found, including
several Sequoias (allied to the gigantic Wellingtonia of
California), with species of Thujopsis and Salisburia now pecu-
liar to Japan. There are also beeches, oaks, planes, poplars,
maples, walnuts, limes, and even a magnolia, two cones of which
have recently been obtained, proving that this splendid tree not
only lived but ripened its fruit within the Arctic circle. Many
of the limes, planes, and oaks were large-leaved species, and
both flowers and fruit, besides immense quantities of leaves, are
in many cases preserved. Among the shrubs were many ever-
greens, as Andromeda, and two extinct genera, Daphnogene and
M'Clintockia, with fine leathery leaves, together with hazel,
blackthorn, holly, logwood, and hawthorn. Potomogeton,
Sparganium, and Menyanthes grew in the swamps, while ivy
and vines twined around the forest trees, and broad-leaved ferns
grew beneath their shade. Even in Spitzbergen, as far north as
lat. 78 56', no less than 131 species of fossil plants have been
obtained, including Taxodium of two species, hazel, poplar,
alder, beech, plane-tree, and lime. 2 Such a vigorous growth of
trees within 12 of the pole, where now a dwarf willow and a
few herbaceous plants form the only vegetation, and where the
ground is covered with almost perpetual snow and ice, is truly
remarkable.

The identity of so many of the fossils with Miocene species of
Central Europe and Italy not only proves 'that the climate of
Greenland was much warmer than it is now, but also rendersit
probable that a much more uniform climate prevailed over the
entire northern hemisphere. This is also indicated by the
whole character of the Upper Miocene Flora of Central Europe,
which does not necessitate a mean temperature very much
greater than exists at present, if we suppose such absence of

1 Ilccr, ' Flora Fossilis Arctica,' and 'Fossil-Flora von Alaska,' 18G9.

2 Heer, ' Miocene Flora and Fauna of Spitzbergen.' Stockholm, 1870*



224 LOWER MIOCENE, BELGIUM. [CH. xv.

winter cold as is proper to insular climates. Professor Heer
believes that the mean temperature of North Greenland
must have been at least 30 higher than at present, while an
addition of 10 to the mean temperature of Central Europe
would probably be as much as was required. The chief locality
where this wonderful flora is preserved is at Atanekerdluk in
North Greenland (lat. 70), on a hill at an elevation of about
1,200 feet above the sea. There is here a considerable succes-
sion of sedimentary strata pierced by volcanic rocks. Fossil
plants occur in all the beds ; and the erect trunks as thick as a
man's body which are sometimes found, together with the abun-
dance of specimens of flowers and fruit in good preservation,
sufficiently prove that the plants grew where they are now
found. At Disco island and other localities on the same part of
the coast, good tertiary coal is abundant, interstratified with
beds of sandstone in some of which fossil plants have also been
found, similar to those at Atanekerdluk.

lower Miocene, Belgium. The upper Miocene Bolder-
berg beds, mentioned at p. 206, rest on a Lower Miocene for-
mation called the Rupelian of Dumont. This formation is best
seen at the villages of Rupelmonde and Boom, ten miles south
of Antwerp, on the banks of the Scheldt, and near the junction
with it of a small stream called the Rupel. A stiff" clay abound-
ing in fossils is extensively worked at the above localities for
making tiles. It attains a thickness of about 100 feet, and,
though very different in age, much resembles in mineral cha-
racter the ' London Clay/ containing, like it, septaria or con-
cretions of argillaceous limestone traversed by cracks in the
interior, which are filled with calc-spar. The shells, referable
to about forty species, have been described by MM. Nyst and
De Koninck. Among them Leda (or Nuculd) Deshayesiana (see
fig. 159) is by far the most abundant ; a fossil unknown as yet

Fig. 159.




Leda (Nucula) Deshayesiana, Nyst.

in the English tertiary strata, but when young much resembling
Leda amygdaloides of the London Clay proper (see fig. 216,
p. 249). Among other characteristic shells are Pecten Hceniny-
hausii, and a species of Cassidaria, and several of the genus
Pkurotoma. Not a few of these testacea agree with English



en. xv.] LOWER MIOCENE OP GERMANY. 225

Eocene species, such as Action simulatus, Sow., Cancellaria
evulsa, Brander, Corbula pimm (fig. 161), and Nautilus (Aturia)
ziczac. They are accompanied by many teeth of sharks, as
Lamna contortickus, Ag., Oxyrhina xipJwdon, Ag., Carcharodon
anyustidens (see fig. 199, p. 245), Ag., and other fish, some of
them common to the Middle Eocene strata.

Kleyn Spawen beds. The succession of the Lower Miocene
strata of Belgium can be best studied in the environs of Kleyn
Spawen, a village situated about seven miles west of Maestricht,
in the old province of Limburg, in Belgium. In that region,
about 200 species of testacea, marine and freshwater, have been
obtained, with many foraminifera and remains of fish. In none
of the Belgian Lower Miocene strata could I find any nuinmu-
lites ; and M. d'Archiac had previously observed that these
foraminifera characterise his ' Lower Tertiary Series,' as con-
trasted with the Middle, and they therefore serve as a good test
of age between Eocene and Miocene, at least in Belgium and the
North of France. 1 Between the Bolderberg beds and the
Rupelian clay there is a great gap in Belgium, which seems,
according to M. Beyrich, to be filled up in the Xorth of Ger-
many by what he calls the Sternberg beds, and which, had
Dumont found them in Belgium, he might probably have
termed Upper Rupelian.

lower Miocene of Germany. Rupelian Clay of Hermsdorf)
near Berlin. Professor Beyrich has described a mass of clay,
used for making tiles, within seven miles of the gates of Berlin,
near the village of Hermsdorf, rising up from beneath the sands
with which that country is chiefly overspread. This clay is
more than forty feet thick, of a dark bluish-grey colour, and,
like that of Rupelmonde, contains septaria. Among other shells,
the Leda Deshayesiana, before mentioned (fig. 159), abounds,
together with many species of Pleurotoma, Voluta, &c. , a certain
proportion of the fossils being identical in species with those of
Rupelmonde.

Mayence basin. An elaborate description has been published
by Dr. F. Sandberger of the Mayence tertiary area, which
occupies a tract from five to twelve miles in breadth, extending
for a great distance along the left bank of the Rhine from
Mayence to the neighbourhood of Manheim, and which is also
found to the east, north, and south-west of Frankfort. M. de
Koninck, of Liege, first pointed out to me that the purely
marine portion of the deposit contained many species of shells
common to the Kleyn Spawen beds, and to the clay of Rupel-
monde, near Antwerp. Among these he mentioned Cassidaria

1 D'Arcbiac, Monogr., pp. 79, 100.

L3



226



LOWER MIOCENE OF CROATIA.



[CH. XV.



Tritonium argutum, Brander (T. flandricum, De
Koninck), Tornatella simulata, Aporrhais Sowerbyi, Ledn DC-
shayesiana (fig. 159), Corbula pisum (fig. 161, p. 228), and others.

lower Miocene beds of Croatia. The Brown Coal of
Radaboj, near Agram, in Croatia, not far from the borders of
Styria, is covered, says Yon Buch, by beds containing the
marine shells of the Vienna basin, or, in other words, by Upper
Miocene or Falunian strata. They appear to correspond in
age to the Mayence basin, or to the Rupelian strata of Belgium.
They have yielded more than 200 species of fossil plants, de-
scribed by the late Professor Unger. These plants are well
preserved in a hard marlstone, and contain several palms ;
among them the Sabal (fig. 154, p. 220), and another genus
allied to the date-palm, Phcenicites spectabilis. The only abun-
dant plant among the Radaboj fossils which is characteristic of
the Upper Miocene period is the Populus mutabilis, whereas no
less than fifty of the Radaboj species are common to the more
ancient flora of the Lower Molasse of Switzerland.

The insect fauna is very rich, and, like the plants, indicates a
more tropical climate than do the fossils of QEningen presently
to be mentioned. There are ten species of Termites, or white
ants, some of gigantic size, and large dragon-flies with speckled
wings, like those of the Southern States in North America ;
there are also grasshoppers of considerable size, and even the
Lepidoptera are not unrepresented. In one instance, the pat-
Fig. 160.




Vanessa Pluto ; nat. size. Lower Miocene, Radaboj, Croatia.

tern of a butterfly's wing has escaped obliteration in the marl-
stone of Radaboj ; and when we reflect on the remoteness of
the time from which it has been faithfully transmitted to us,
this fact may inspire the reader with some confidence as to the



CH. xv.] LOWER MIC GENE OF ITALY. 227

reliable nature of the characters which other insects of a more
durable texture, such as the beetles, may afford for specific
determination. The Vanessa (fig. 160) retains, says Heer,
some of its colours, and corresponds with V. Hadena of
India.

Professor Beyrich has made known to us the existence of a
long succession of marine strata in North Germany, which lead
by an almost gradual transition from beds of Upper Miocene
age to others of the age of the base of the Lower Miocene.
Although some of the German lignites called Brown Coal
belong to the upper parts of this series, the most important of
them are of Lower Miocene date, as, for example, those of the
Siebengebirge, near Bonn, which are associated with volcanic
rocks. Professor Beyrich confines the term ' Miocene ' to those
strata which agree in age with the faluns of Touraine, and he
has proposed the term ' Oligocene ' for those older formations
called Lower Miocene in this work.

Lower Miocene of Italy. In the hills of which the Superga
forms a part (see above, p. 208) there is a great series of Tertiary
strata which pass downwards into the Lower Miocene. Even
in the Superga itself there are some fossil plants which, accord-
ing to Heer, have never been found in Switzerland so high as
the marine Molasse, such as Banksia longifolia, and Carpinus
grandis. In several parts of the Ligurian Apennines, as at
De'go and Carcare, the Lower Miocene appears, containing
some nummulites, and at Cadibona, north of Savona, freshwater
strata of the same age occur, with dense beds of lignite enclos-
ing remains of the Anthracotherium magnum and A. minimum,
besides other mammalia enumerated by Gastaldi. In these
beds a great number of the Lower Miocene plants of Switzerland
have been discovered.

lower Miocene of England Hempstead beds. We have
already stated that the Upper Miocene formation is nowhere
represented in the British Isles ; but strata referable to the
Lower Miocene period are found both in England, Scotland,
and Ireland. In the Hampshire basin these occupy a very
small superficial area, having been discovered by the late
Edward Forbes at Hempstead near Yarmouth, in the northern
part of the Isle of Wight, where they are 170 feet thick, and
rich in characteristic marine shells. They overlie the upper-
most of an extensive series of Eocene deposits of marine,
brackish, and freshwater formations, which rest on the Chalk
and terminate upwards in strata corresponding in age to the
Paris gypsum, and containing the same extinct genera of quad-
rupeds, Palxotlier'mm, Anoplotheriwn, and others which Cuvier



228



LOWER MIOCENE OF ENGLAND.



[CH. XV,



first described. The following is the succession of these Lower
Miocene strata, most of them exposed in a cliff east of Yar-
mouth.

1. The uppermost or Corbula beds, consisting of marine
sands and clays, contain Valuta Rathieri, a characteristic Lower
Miocene shell ; Corbulapisum (fig. 161), a species common to the
Upper Eocene clay of Barton ; Cyrena semistriata (fig. 162),
several Cerithia, and other shells peculiar to this series.



Fig. 161.



Fig. 162.





Corbulapisum. Hemps tead Beds,
Isle of Wight.



Cyrena semistriata.
Hemps tead Beds.



2. Next below are freshwater and estuary marls and carbon-
aceous clays, in the brackish- water portion of which are found
abundantly Cerithium plicatum, Lam. (fig. 163), C. elegans (fig.
164), and C. tricinctum ; also Eissoa Chastelii (fig. 165), a very
common Kleyn Spawen shell, which occurs in each of the
four subdivisions of the Hempstead series down to its base,
where it passes into the Bembridge beds. In the freshwater
portion of the same beds Paludina lenta (fig. 166) occurs ; a

Fig. 163. Fig. 164.





Fig. 165.



Fig. 166.





CeritMum plicatum,
Lam. Hempstead.



CeritJiitim elegans. Rissoa Cliastelii, Nj
Hempstead. Sp. Hempstead, ]

of Wight.



Paludina lenta.
Hempstead Bed.



shell identified by some conchologists with a species now living,
P. unicolor ; also several species of Limnoeus, Planorbis, and
Unio.

3. The next series, or middle freshwater and estuary marls,
are distinguished by the presence of Melania fasciata, Paludina



en. xv.] LIGNITES OF BOVEY TEACEY. 229

knta, and clays with Gypris ; the lowest bed contains Cyrena
semistriata (fig. 162), mingled with Cerithia and a Panop&a.

4. The lower freshwater and estuary marls contain Melania
costata, Sow., Melanopsis, &c. The bottom bed is carbonaceous,
and called the ' Black band,' in which Ri$soa Chastclii (fig. 165),
before alluded to is common. This bed contains a mixture of
Hempstead shells with those of the underlying Upper Eocene
or Bembridge series. The mammalia, among which is Hyopo-
tamus bovinus, differ, so far as they are known, from those of
the Bembridge beds. The Hyopotamus belongs to the hog
tribe, or the same family as the Anthracotherium, of which
seven species, varying in size from the hippopotamus to the
wild boar, have been found in Italy and other parts of Europe
associated with the lignites of the Lower Miocene period.

Among the plants, Professor Heer has recognised four species
common to the lignite of Bovey Tracey (a Lower Miocene for-
mation presently to be described) : namely Sequoia Couttsiae,
Heer ; Andromeda reticulata, Ettingsh. ; Nelumbium (Nymphsed)
Doris, Heer; and Carpolithes Websteri, Brong. 1 The seed-
vessels of Chara medicaginula, Brong., and C. helicteres are
characteristic of the Hempstead beds generally.

lignites and Clays of Bovey Tracey, Devonshire. Sur-
rounded by the granite and other rocks of the Dartmoor hill
in Devonshire, is a formation of clay, sand, and lignite, long
known to geologists as the Bovey Coal formation, respecting
the age of which, until the year 1861, opinions were very
unsettled. This deposit is situated at Bovey Tracey, a village
distant eleven miles from Exeter in a south-west, and about us
far from Torquay in a north-west, direction. The strata extend
over a plain nine miles long, and they consist of the materials
of decomposed and worn-down granite mixed with vegetable
matter, and have evidently filled up an ancient hollow or lake-
like expansion of the valleys of the Bovey and Teign.

The lignite is of bad quality for economical purposes, having
a great admixture of iron pyrites, and emitting a sulphurous
odour ; it has, however, been successfully applied to the baking
of pottery, for which some of the fine clays are well adapted.
Mr. Pengelly has confirmed Sir H. De la Beche's opinion that
much of the upper portion of this old lacustrine formation has
been removed by denudation. 2

At the surface is a dense covering of white clay and gravel
with angular stones probably of the Pleistocene period, for in

1 Pengelly, preface to ' The Lignite 2 Phil. Trans., 1863. Paper by
Formation of Bovey Tracer,' p. xvii.: W. Pengelly, F.K.S., and Dr. Oswald
London, 1863. Heer.



230 LEAF-BEDS OF MULL, IN SCOTLAND. [CH. xv,

the clay are three species of willow and the dwarf birch, Betula
nana, indicating a climate colder than that of Devonshire at the
present day.

Below this are Lower Miocene strata about 300 feet in thick-
ness, in the upper part of which are twenty-six beds of lignite,



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