Introduction Wenn sich die Weisen nicht zuweilen verirteten, so m ssten alle Narren versagen. .Johann Wolfgang von Goethe I may freely, without shame, leave some obscurities to happier industry, or future information. .Samuel Johnson Checklists and catalogues are regarded with disdain by some biologists who consider them mere hackwork, compiled from literature and devoid of phylogenetic insights. Systematists who are actually involved in transferring knowledge about the characteristics, relationships, and distribution of poorly-known organisms from the alpha to gamma level (thus making it accessible to theoreticians) tend to be more generous. There are no references more fundamental than comprehensive summaries of current knowledge, and the efforts of assembling and organizing information from a vast polyglot literature into a compact and manageable form are highly appreciated by subsequent users. A checklist or catalog is often the catalyst that initiates or stimulates active interest in some neglected taxon, and whether one concurs with the details of presentation is immaterial so long as all the facts are available. It is often overlooked that the basic purpose of such compendia is to facilitate their own obsolescence. An increasing interest in tropical biotas during the past several decades allows a guarded hope that the importance of millipeds in such ecosystems will be recognized and investigated. Although three annotated checklists have been published (West Indies: Chamberlin, 1918; North America: Chamberlin & Hoffman, 1958, and Middle America: Loomis, 1968 respectively), they are now obsolete and inadequate. As the faunas of these regions are now amenable to a revised treatment, this occasion is taken to provide a comprehensive, updated, summary of the diplopod fauna of the entire area north of the South American mainland. Although the lists mentioned provided the baseline resources, the addition of information they did not contain has required consultation of all original references de novo. Organizational Details The area The names applied to the major geographic areas of the Western Hemisphere have been both highly diverse and highly inconsistent. Sometimes Mexico is included in North America , sometimes in Central America , sometimes Central America has included Mexico, sometimes only the countries from Guatemala to Panama. Some maps extend North American all the way to the border of Colombia. The West Indies have rarely been associated with any parts of the mainland under an inclusive name. 2 VIRGINIA MUSEUM OF NATURAL HISTORY SPECIAL PUBLICATION 8 Existing data are simply organized by political units, and will be for a long time. Since the definitions and terminology for the region between the United States and northernmost South America have been arbitrary and apparently very subjective anyhow, I feel no compunction in adopting my own equally arbitrary concepts and categories for the purposes of this list. It must be obvious that political boundaries are in the present state of knowledge more pragmatically useful than anything approaching biogeographic regions (e.g., Nearctic vs. Neotropical, each with its local subdivisions). The fauna of the West Indies has clearly been derived from land masses to the west and south, and there being no endemic components, there is no reason to award a special status to these islands. My operational categories are defined as follows: I. North America: United States and Canada. II. Middle America (the terms Mesamerica and Mesamerican are frequently used in the text) 1. Mexico 2. Central America: Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, Panama 3. West Indies A. Greater Antilles: Cuba, Jamaica, Puerto Rico, Hispaniola, Bahamas, Turks and Caicos, Virgin Islands, and Saint Croix (in effect, all islands west of the Anegada Passage) B. Lesser Antilles: all islands south of the Anegada Passage, from Anguilla to Grenada. III. South America: all countries south and east of (and including) Colombia, Venezuela, and the continental islands from Aruba to Tobago, which are geographically part of South America even if frequently included in the Lesser Antilles on some maps. In this respect, I depart from the precedent of Pocock (1894), Chamberlin (1918), and Loomis (1934), all of whom included Trinidad and Tobago in their concept of West Indies . Information content The material presented in the following pages is strictly taxonomic, not bibliographic. No attempt is made to cite all published references to the included taxa. A departure from the formats of the 1958 and 1968 lists is omission of keys to orders and families. For these to be accurate and meaningful, extensive illustration would be required. However, citations to relevant taxonomic sources (keys, revisions, redescriptions, etc.) are included under the pertinent heading level. Full reference to original description, type locality, and location of type specimens for all names is provided to enhance accessibility to names currently treated as junior synonyms since the disposition of such names is usually subjective and open to subsequent revision. The user is spared the trouble of having to go back to original sources for "synonym information." The treatment of taxa at all levels reflects the most recent published concepts, except in a few cases in which the compiler holds a different opinion and explains his position in a short discourse under the relevant category heading. Entries for the 2,167 species provisionally admitted as valid include the usual reference citation to original description, type locality, and location of holotype (or syntypes), the last shown parenthetically by acronym code (the list is given in the following paragraph). Synonyms are listed chronologically with the same information; for widespread anthropochoric species only those synonyms based upon specimens taken from within the area of coverage. Known species ranges are given in very general terms, supplemented by reference to any published distribution maps. The absence of a sideheading Range: implies that the taxon is known only from the type locality (or very close thereto: numerous localities in a single county or similar unit are usually not specified). The only fossil taxa recorded are a few of Tertiary or Quarternary age, some of which may be the same as species still existing in or near their type localities. HOFFMAN: CHECKLIST OF THE MILLIPEDS OF NORTH AND MIDDLE AMERICA 3 Citations to journals are spelled out with the standard title abbreviations rather than given simply as a year and page number. This takes up a little more space, but obviates the necessity to refer to a list of the cited papers in a terminal bibliography which I personally consider an unnecessary nuisance. Additional bibliographic information, inserted at the relevant place throughout the text, is preceded by explanatory terms. A special case is provided by the "Bulletin of the University of Utah" which for many years appeared with a separate category called the "Biological Series", with its own independent volume numbering system. Thus volume 31, no. 11, was simultaneously volume 6, no. 4, of the Biological Series. As I believe that most libraries would catalog this periodical in terms of its primary issuance system, I have disregarded the "Biological Series" subseries and cite all references in terms of the primary volume numbers. This is in contrast to the checklists by Chamberlin & Hoffman (1958) and Loomis (1968), as well as most references to Chamberlin s papers by recent investigators. It is however consistent with the usage of Jeekel s Nomenclator (1971). Various journals (e.g., the Bulletin of the University of Utah, the Bolletino of the Museum of Zoology and Comparative Anatomy of the University of Torino) have appeared as volumes composed of sequential articles, each with its own pagination. In such cases, I have included the relevant article number parenthetically after the volume number, thus 60(8): . When pagination has run continuously throughout the volume, it has seemed unnecessary to cite the article number. Some journals (including the Proceedings of the U. S. National Museum), have alternated both the article and continuous pagination at different times, requiring attention to this point. The bibliography contains just over 770 entries, and contains only those papers of strictly taxonomic and/or nomenclatorial content except in a few cases in which a treatment of biology, structure, or distribution contains relevant information. Entries are thought to be complete up to the end of 1998; a few still in press are included. Type localities Generally, type localities are cited in standard size order, from the locality itself upward through larger political units; this is often a reverse of the original sequence as printed. The type localities of species described in languages other than English are often quoted in the original when this seemed desireable (e.g., when something might be lost in translation). I have tried to locate many places that were not clearly specified in the original description, but not consistently so - some things are left for a later generation to run down. Many place names, especially in Guatemala, are those of small ranches (fincas) not shown on most maps. Where possible I have provided distance and direction from the nearest mapped settlement. Cuba has provided a special problem in that the original four provinces have been recently divided into fourteen and I am not sure I have correctly allocated all localities