Ultrastructural studies on graptolites - Urbanek, Adam.; Towe, Kenneth M. (Washington : Smithsonian Institution Press, 1974)
1. The periderm and its derivatives in the Dendroidea and in Mastigograptus.--2. The periderm and its derivatives in the Graptoloidea.
Includes bibliographies.
Keywords: Graptolites; Paleontology -- Ordovician