21. Argillaceous limestone, marl clay. Mollusca, reptiles, and fish analogous to the Oölitic.
I. Trias.
22. Upper Trias. Red, gray, green, blue, and white marls, and sandstone, with gypsum. Batrachian reptiles.
23. Middle Trias. Compact grayish limestone, with beds of muschelkalk, of dolomite and gypsum.
24. Lower Trias. Plants different for the most part.
IV. Primary. J. Permian.
25. Upper Permian. Yellow magnesian limestone. Organic remains both animal and vegetable, more allied to primary than to secondary period.
26. Lower Permian. Marl slate. Thecodont saurians, heterocercal fish, etc.
K. Carboniferous.
27. Coal measures. Great thickness of strata of fluvio-marine origin, with beds of coal of vegetable origin, based on soils retaining roots of trees. Oldest of known reptiles. Sauroid fish.