GEOGNOSY AND GEOLOGY. 161 
separate sockets. It forms the transition from the Lacertide to the 
crocodiles. 
Pl. 46, fig. 10, exhibits an ideal section of the copper slate formation. 
Immediately on the carboniferous sandstone (qa), lies the red sandstone (1). 
against which rests the white red sandstone (2). Then come copper slate 
(3), zechstein (4), a dolomitic rock (5), asche (6), old floetz gypsum with 
foetid limestone (7), and marl beds (8). The whole is covered by the 
variegated sandstone (0). 
Rock Salt Formation (Trias. Terrain salifére. Group triasique). 
The rock salt formation marks the commencement of the secondary 
formation of Elie de Beaumont, and immediately follows the copper slate. 
The principal rock species are sandstones, limestones, and marls, so 
arranged that. the sandstones occupy the upper and lower portions, including 
the limestones in the middle, both species being combined by marly forms. 
Gypsum, karstenite, and rock salt are subordinate members, the latter of 
which, from its extensive distribution and intrinsic importance, has given 
name to the formation. Rock salt is generally accompanied by gypsum and 
karstenite. 
The only metallic minerals of importance are galena, electric calamine. 
and hydrated oxyde of iron. Fossils occur in immense accumulations of 
individuals, although genera are few: they characterize the single groups 
and series of beds so perfectly, that no other formation can be compared to 
the rock salt in this respect: organic remains are, therefore, of especial 
importance for this formation. Three groups of the rock salt may be 
distinguished, sufficiently entitled to separation. 
a. Variegated Sandstone Group. This is formed by sandstones of 
mostly red or reddish brown color, accompanied by clay and marl masses. 
Subordinate masses of the variegated sandstone are: quartz rock, clay 
quartz, limestone, sometimes oolite, gypsum, karstenite, and rock salt. 
Among the fossils are vegetable remains of a terrestrial character. This 
group separates into three subdivisions; the first of which, the Vosges 
sandstone, is of rarest occurrence. 
The Vosges sandstone-is sometimes argillaceous, sometimes quartzose, 
sometimes hard, sometimes soft, either fine or coarse grained, and in single 
cases inclined more or less to quartz rock. The color is generally red, and 
the beds sometimes exhibit a thickness of 1000 to 1200 feet. It is mostly 
distinctly laminated, lying more or less horizontally, and free from 
subordinate beds and from fossils. It occupies the highest part of the 
Vosges and of the Schwarzwald. 
The middle division, that of the variegated sandstone, does not exhibit 
this uniformity; the sandstones are sometimes argillaceous, sometimes 
marly, and of different degrees of hardness, with the most diversified 
coloration ; red predominates. Mica, chlorite, and talc, not seldom lie 
parallel to the planes of cleavage, as also dendrites of black oxyde of 
manganese. Calcareous and brown spar are often found crystallized in 
drusy cavities, these being not seldom found with a red barytes. The 
stratification is very complete, sometimes finely laminated, this being 
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