Subject ASC0001fsf
The Quarterly journal of the Geological Society of London.
v.7 (1851), Page 110 (1851)
Smithsonian Libraries
BHL Page 34984231
Keywords
Chalk formation Germany Cretaceous rocks Chalk sand fossils chalk ormation chalk-formation chalk vegetable remains cretaceouos rocks table algae observations remains vegetal aix-la-chapelle district proportions stratigraphy upper chalk middle chalk lower chalk Aix-la-Chapelle Aachen cretaceous