860 STRATIGRAPHICAL GEOLOGY.  [Boox VI. . 
(Egeln marine beds (Ostrea ventilabrum, Arca appendiculata, Cardita 
Dunkeri, Cardium Hausmanni, Cytherea Solandri, Cerithium levum, 
Pleurotoma Beyrichi, P. subconoidea, Voluta decora, &c., and corals of 
the genera Turbinolia, Balanophyllia, Caryophyllia, Cyathina). 
Amber beds of Konigsberg—containing a bed (4 to 5 feet) of glauconitie 
sand, with abundant pieces of amber. The latter, derived from several 
species of conifers, have yielded a plentiful series of insects, arachnids, and 
myriapods, while the sands contain lower Oligocene marine mollusca. 
Lower Brown-coal series—sands, sandstones, conglomerates, and clays with 
interstratified varieties of brown-coal (pitch-coal, earthy lignite, paper 
coal, wax-coal, &c.), a single mass of which sometimes attains a thickness 
of 100 feet or more. These strata may be traced intermittently over 
a large area of northern Germany. The flora of the brown-coal is largely 
composed of conifers (Taxites, Twxoxylon, Cupressinoxylon, Sequoia, &c.), 
but also with Quercus, Laurus, Cinnamomum, Magnolia, Dryandroides, 
Ficus, Sassafras, Alnus, Acer, Juglans, Betula, and palms (Sabal, Flabel- 
lavia). The general aspect of this flora most resembles that of the 
southern States of North America, but with relations to earlier tropical 
(floras having Indian and Australian affinities. 
Lower. 
Switzerland.1—Nowhere in Europe do Oligocene strata play so 
important a part in the scenery of the land, or present on the whole so 
interesting and full a picture of the state of Hurope when they were 
deposited, as in Switzerland. Rising into massive mountains, as in the 
well-known Righi and Rossberg, they attain a thickness of more than 
6000 feet. While they include proofs of the presence of the sea, they 
have preserved with marvellous perfection a large number of the plants 
which clothed the Alps, and of the insects which flitted through the 
woodlands. They form part of a great series of deposits which have 
been termed ‘“ Molasse” by the Swiss geologists. The Molasse was - 
formerly considered to be entirely Miocene. The lower portions, how- 
ever, are now placed on the same parellel with the Oligocene beds of 
the regions lying to the north, and consist of the following subdivisions : 
Lower brown-coal or red Molasse (Aquitanian stage)—the most massive member 
of the Molasse, consisting of red sandstones, marls, and conglomerates 
(Nagelfluh), resting upon variegated red marls. It contains seams of 
lignite, and a vast abundance of terrestrial vegetation. 
Lower marine Molasse (Tongrian stage)—sandstone containing marine and 
brackish-water shells, among which are Ostrea cyathula, O. longirostris, 
Cyrena semistriata, Pectunculus obovatus, Cerithium plicatum. 
By far the larger portion of these strata is of lacustrine origin. 
They must have been formed in a large lake, the area of which probably 
underwent gradual subsidence during the period of deposition, until in 
Miocene times the sea once more overflowed the area. We may form 
some idea of the importance of the lake from the fact already stated, that 
the deposits formed in its waters are upwards of 6000 feet thick. Thanks 
to the untiring labours of Professor Heer, we know more of the vegeta- 
tion of the mountains round that lake during Oligocene and Miocene 
time than we do of that of any other ancient geological period. The 
woods were marked by the predominance of an arborescent sub-tropical 
vegetation, among which evergreen forms were conspicuous, the whole 
having a decidedly American aspect. Among the plants were palms of 
American type, the Californian coniferous genus Sequoia, alders, birches, 
figs, laurels, cinnamon-trees, evergreen oaks, and other plants (see pp. 
862, 867). 
1 Heer’s Urwelt dev Schweiz. 
~ Sed at 
* + =n 7 
; 
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