Receptaculitids are extinct high-level fossils that provide a window into the history of life. After the discovery and analysis of a deposit of phosphatized receptaculitids on the Baltic Sea island of Öland, the authors conclude that receptaculitids possess an attribute not found in any other group of organisms, living or fossil.

Dedication. Table of Contents. List of Illustrations. Preface. I. Introduction. II. The Biography of an Idea. III. Geology. IV. Morphological Characteristics of Fisherites orbis. V. Morphology of a Merom. VI. Quaestio disputata: Morphological Reductionism. VII. Summary and Beyond.Addendum: Horns of Dilemma: Phosphatization. Appendix I: Taxonomic Assignment of Receptaculitids. Appendix II: Names Receptaculitid Taxa. References. Authors Index. Taxonomic Index. Subject Index.