Page:Bergey's manual of determinative bacteriology.djvu/13

 PREFACE TO SEVENTH EDITION The general format of the seventh edition of differs but little from that of the sixth edition. However, examination will reveal many changes in the content as the result of a thoroughgoing revision. Among these the following seem to be worthy of special comment.

The most obvious change is that of the separation into two volumes of the material comparable to that which appeared in the sixth edition. The present volume is entitled the seventh edition of This  contains an outlined classification of the bacteria and the descriptions of the taxa from Class to Species and Subspecies, together with the appropriate keys. Nearly all species regarded as having been inadequately described or that could not be definitely placed have been excluded, together with many of the less important synonyms of the accepted species. These, together with the index to all the literature of both accepted and poorly described organisms have been transferred to a volume to be known as the. The latter volume will include all descriptions and citations to species formerly found as appendices or indefinitely placed as species incertae sedis. The host and habitat index will also be found in the. The net result is that the itself contains descriptions of many more species with more adequate descriptions than have former editions; the transfer of much material to the  has meant a reduction in the number of pages and a book of more convenient size and greater usefulness. The should prove to be an invaluable tool for the research microbiologist, containing, as it will, references to the whole field of systematic bacteriology and an index to the names of described species, both valid and invalid.

Much material of historical value and interest in the sixth and earlier editions of the has been excluded, not because it is lacking in real value to the student, but because repetition of its publication is now unnecessary.

This edition of the represents the coordinated results of the work of one hundred contributors, about thirty-five more than assisted in preparing the sixth edition. The contributors to the Manual are to be regarded in all nomenclatural matters as strictly the authors of their sections. All new names of taxa and the names of all new combinations are to be ascribed to these authors, and not to the editors of the. Contributors from countries other than the United States are more numerous than in the earlier editions. In other words, the is rapidly assuming the character of an international publication. To all of these contributors the sincere thanks of the Board of Editors, and particularly of the Editor-in-Chief, are due. The seventh edition is a tribute to the patience, care and scientific acumen of these individuals. Special note should be taken of the assistance rendered in the office of the Editor-in-Chief by Mr. Erwin Lessel, Miss Maude Hogan, Mrs. Eleanore Heist Clise and Mrs. Margaret Edson Breed. ix