Familiarity with the individuals and organizations connected with the production of motion pictures during the pioneer period was essential to the identification as motion pictures of works registered as photographs in the Copyright Office. Mr. Walls is uniquely fitted to make this selection. He is at present Curator of the Motion Picture Collection of the Academy of Motion Picture Arts and Sciences. Previously he was for several years on the staff of the Copyright Office and during that period was interested in the records of early motion pictures which existed in the files of the Office, including the paper prints which were deposited at the time of the registration of many of these motion pictures. Later he became Curator of the Motion Picture Collection of the Library of Congress and Reference Assistant in the Motion Picture Division. He has had, therefore, long and intensive experience in working with these early motion pictures and he is also familiar with the organization of the records of the Copyright Office. The preparation of the catalog for printing was principally the work of the staff of the Cumulative Section of the Cataloging Division of the Copyright Office. Mr. Walls reviewed all entries after they were transcribed from the record books and assisted in editing them by adding in brackets, whenever he could do so without additional research, explanatory information in those cases in which the titles are not fully self-explanatory. Except for these bracketed phrases the information appearing in the entries in the catalog is that on record in the Copyright Office. In the case of each entry the name of the copyright claimant is that given in the record book. Any information relating to renewal copyrights or to subsequent changes of ownership recorded in the Copyright Office can be ascertained upon request and upon payment to the Register of Copyrights of the fee specified in the law for the conduct of a search of the records. In addition, information relating to renewal copyrights can be secured by referring to the issue of the _Catalog of Copyright Entries_ covering renewal registrations for the particular class of work during the renewal period. In the _Claimant Index_ the name of each claimant is given in the fullest form on record in the Copyright Office with cross-references from variant forms. Full information in regard to the content of the entries in the main section and in the index will be found in the section, _How To Use This Catalog_, p. X. Preface