16 , GEOLOGICAL MEMOIRS. 
marshy deposits. In this respect the slates of Rothwaltersdorf, 
which constitute a lenticular intercalary deposit in the upper Grau- 
‘ wackes of the Culm, are particularly interesting from their combi- 
nation of typical Culm fossils, such as Posidonomya Becheri, Cala- 
mites transitionis, Cyclopteris polymorpha, C. dissecta and other 
plants, with fossils of the typical Carboniferous limestone. Vege- 
table remains may certainly be transported from dry land or fresh 
waters into marine deposits, but not such an abundance of decidedly 
marine forms into fresh- or brackish-water deposits. The presence 
of Posidonomya Becheri at Rothwaltersdorf, and at no other locality, 
may be accidental; but as it is always found associated with remains 
of plants, itis allowable to suppose that it is a freshwater form 
carried into the sea with those plant-remains. The Culm, with its 
conglomerates and micaceous sandstones, is a coast formation; and 
the coast on which it was deposited was strongly acted upon by the 
waves, whilst the finer mud was thrown down in the quieter parts. 
[Count M.] 
3. GEoLoGy of the ODENWALD (ENviRoNns of HEIDELBERG). 
By Prof. M. N. Benucxez. 
[Proc. Imp. Geol. Inst. Vienna, April 5, 1870.] 
Tue Granites and Quartz-porphyries of this district are immediately 
overlain by Dyas deposits (which have but a small extent both ver- 
tically and horizontally), partly Old Red Sandstone Conglomerates 
and partly Marls, Dolomite, and iron-ores, with remains of Schizodus 
obscurus, representing the “ Zechstein.” The greater portion of the 
district is occupied by Triassic deposits, of which the Bunter Sand- 
stone is above 1000 feet in thickness, and has furnished the mate- 
rials for the most conspicuous buildings of this region (such as the 
Castle of Heidelberg, the cathedrals of Spires and Worms, &c.). 
The Muschelkalk presents an interesting form intermediate between 
those of Franconia, Thuringia, and Swabia. Jurassic deposits occur 
at the surface only in the basin of Langenbriicken, where the Lias 
and Inferior Dogger are recognized. Tertiary, diluvial, and alluvial 
deposits are of quite local occurrence, [Counr M.] 
