Heidelberg, Carl Winter, 1909. 8vo (23.6 x 16.1 cm). 153 pp.; four plates, ten text figures, several folded tables. Printed front wrapper. = The author, Rudolf Emil Otto Georg Wilckens (1884-1936) described and illustrated well-preserved faunas of, mainly, brachiopods and bivalves, including new species. This is his thesis, with fouble pagination, and a "Lebenslauf". Also published in the Verhandlungen des Naturhistorisch-Medizinischen Vereins zu Heidelberg, but then without his curriculum vitae. Provenance: the names Willi Parie and Alex(ander) Tollmann both handwritten in the top margin of the front wrapper. No rear wrapper. Otherwise a very good copy.