138 ROMER’S DESCRIPTION OF THE CHALK 
The lower beds (6) we consider to be lower greensand ; but we 
doubt whether the upper ones likewise belong to that division, 
or should be referred to the upper greensand and streaked 
chalk-marls (flammen-mergel). We have similar doubts with 
respect to the succession of the deposits between Rippchen and 
Gobbeln ; where the upper, marly, micaceous, soft argillaceous 
stratified sandstones are separated, by a somewhat sandy bed of 
clay, of a light gray colour and about 3 feet in thickness, from 
the lower lighter-coloured and less stratified sandstones, which 
are spotted with iron. 
The so-called ¢ shell-rocks’ at Coschutz, in the vale of Plauen 
exhibit a very remarkable outcrop of this deposit; they form 
five isolated blocks, a few feet in height, projecting in a straight 
line on the declivity of the mountain, and consist of numerous 
shells cemented together by a soft yellowish sandstone. Among 
these shells occur Nerinea Borsoni, Exogyra columba, Cardium 
Hilanum, Turritella granulata ; which will probably justify the 
age here assigned to this deposit. 
The masses of sandstone which occur on the east of Tharandt, 
at Opitz, and to the west at Grullenbourg and Nieder Schéna, 
appear likewise to belong to the lower greensand (quader). The 
fossil plants for which these rocks are remarkable, occur at the 
last-mentioned place: the lower strata of the sandstone, which 
in no respect differs from those above them, alternate several times 
with layers from 3" to 3!* in thickness, of a dark gray micaceous 
schistose clay; and in these are enclosed well-preserved leaves 
of ferns and dicotyledons, among which, apparently, is also 
a Credneria. The ferns are distinct from those of the Weald- 
clay; and the Credneria and other dicotyledons might almost 
induce us to consider the whole sandstone formation of that di- — 
strict as of the same age with that of Blankenburg. . 
Similar relations of the sandstone rocks as at Nieder Schéna, — 
are said to have been exposed to view to the east of Dresden, at 
Quohren. 
The greatest horizontal extent of the lower greensand (quader) ~ 
occurs in the so-called “ Saxon Switzerland,” and in the north- — 
easterly portion of Bohemia. It is there indistinctly stratified, — 
often much rifted and fine or coarse-grained, white or yellowish 
* The precise meaning of the marks attached to these numbers is unknown ~ 
to the Translator. 
