- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
A detailed study of a Llandovery (Silurian) section in a small quarry northeast of Doebra, Germany, has resulted in delineation of seven graptolite zones that show remarkable similarity with British graptolite sequences. The zones in ascending order are Glyptograptus persculptus, Diplograptus acuminatus, D. vesiculosus-Monograptus cyphus, M. gregarius, M. convolutus, M. sedgwickii, and M. turriculatus. Characteristic species of each zone are listed.