The work of the Survey's Geologic Names Committee, including the rudiments of the first compendium, was begun and organized by John B. Patton. Former members of the committee also included T. A. Dawson, Ned M. Smith, Frank H. Walker, and William J. Wayne. The present committee consists of Curtis H. Ault, Henry H. Gray, Nancy R. Hasenmueller, John A. Rupp, and Robert H. Shaver (chairman). Responsibility for the initial organization of work for the revised compendium was divided as follows: Cambrian through Devonian articles, Shaver; Mississippian articles, Gray; and Pennsylvanian articles, Ault.

Committee members are grateful to the several noncommittee members who have contributed many articles to the revised compendium. We, committee members and all authors alike, are also grateful to the several Survey employees who typed and edited the text and prepared the illustrations. We are especially indebted for the valuable advice rendered by the many reviewers, each of whom read one or more sets of articles as were appropriate to his or her interests. All the authors also served as critics of articles other than their own; those critics who were not also authors were: G. L. Carpenter, John A. Rupp, and Dan M. Sullivan, all of the Indiana Geological Survey, Bloomington; J. A. Fagerstrom, University of Nebraska, Lincoln; Helen Hay, Earlham College, Richmond, Ind. ; Markes E. Johnson, Williams College, Williamstown, Mass. ; Roy C. Kepferle, Eastern Kentucky University, Richmond; William A. Oliver; Jr. , U. S. Geological Survey, Washington, D. C. ; Dale R. Spatting, Southwest State University, Marshall, Minn. ; and Jack A. Sunderman, Indiana and Purdue Universities, Fort Wayne.

We remain very much aware of the work of many pioneers in Indiana stratigraphy, some of whom are listed in the first compendium, and the revised compendium is rededicated to them and is built from the foundation that they provided. Much of that foundation was summarized by Edgar R. Cumings (1922) in his "Nomenclature and Description of the Geological Formations of Indiana. " The "Handbook of Indiana Geology (Logan and others, 1922), in which Cumings's summary is published, is still one of the most frequently cited publications on Indiana geology. Much information in Cumings's chapter, particularly paleontologic, historical, and bibliographic, is not repeated in the revised compendium, which, therefore, forms a supplement to the "Handbook of Indiana Geology" is some respects.