Palaeontolographica America. Vol. 5. North American ambonychiidae (Pelecypoda)

The present work was carried out in partial fulfillment of the requirements for the degree of Doctor ol Philosophy at the University of Cincinnati. The author Blends his sincere thanks to the members of the Departments of Biological Sciences and Geology at the University fur generously giving of their time and knowledge during the preparation of the manuscript. Especial thanks is extended to Dr. К. Е. Caster, under whose direction the manuscript was prepared. I le was a source ol help and en-tonragement, and his invaluable library made many rare «inks readily available to me. 1 am indebted to Dr. Norman П. Newell for reviewing the manuscript and offering many helpful suggestions. To my "wife continuing thanks for proofreading and typing the greater bulk of the manu-Mtipt.

I would like to thank the following individuals for placing museum specimens and type materials at my disposal: Dr. R. L. Batten and Dr. N. D. Newell, American Museum of Natural History; Dr. R. l£. Sloan, University of Minnesota;   J.K.Pope   and    DrR.Rcinhart,  Miami University, Oxford, Ohio; Dr. D. W. Fisher, С F. Kilfoyle, and Dr. L. V. Rickard, New York State Museum; Dr. E. C. Stumm, University of Michigan; Dr. R. S. Hoard-man, Dr. G. A. Cooper, and Dr. E. G. Kauffman, United States National Museum; M. H. Nitecki, Walker Museum, University of Chicago; Dr. A. L. McAlester, Peabody Museum, Yale University; and Dr. E. S. Richardson, Jr., Chicago Natural History Museum.

In appreciation for helpful correspondence 1 would like to thank: Dr. M. J. Copeland, Geological Survey of Canada; Dr. G. M. Kay, Columbia University; Dr. L. S. Kent, Illinois State Geological Survey; Dr. T. Kobayashi, Imperial University of Tokyo; Dr. G. Regnell, Lund University, Lund, Sweden; Dr. B. Ruzicka, Mining University, Ostrava, Czechoslovakia; and Dr. H. Scott, University of Illinois.

The cost of the engraving of the illustrations has been met by a grant from the Graduate School of the University of Cincinnati.