Clays, shales, sands, red and green marls, and alum shale, with occasional layers of beef (fibrous carbonate of lime) […] Chief Beef Beds, Dark (alum) shales with beef and selenite, beds of limestone, and layers of perished shells. Cyrena and Cyrides.
Corbula Beds. Layers of shelly limestone, shale, alum shale, and marl, with beef and selenite.