2 U.S. NATIONAL MUSEUM BULLETIN 266 



contributors to the advances that have been made in our understanding 

 and classification of this group. 



The present checklist has been prepared to overcome some of the 

 difficulties of studying the millipeds of these countries, as presented 

 by the dispersed literature and lack of bibliographies to it. In general, 

 this checklist follows the arrangement of the admirable Checklist of the 

 Millipeds of North America, by R. V. Chamberlin and R. L. Hoffman, and 

 adopts the basic classification system they proposed on pages 7 and 8, 

 except as altered later by the junior author to combine the orders Spiros- 

 treptida and Cambalida, with the latter reduced to a suborder. As in that 

 checklist, keys to all classification categories through families have 

 been included here. 



Citations throughout this checklist, except where they do not apply to 

 the area involved, have been reduced to the last name of the author, 

 followed by the year of publication. Where two or more publications by 

 the same author occurred in the same year, each is indicated by a letter 

 added to the date, i.e., 1935a, 1935b, etc. Full citations for these abbre- 

 viations are given in the bibliography which lists the references appli- 

 cable to the class Diplopoda in Mexico and Central America. 



Where a change or changes have occurred in the use of the original 

 name of a genus or species, such changes are cited in chronological 

 order under the current name. In a few cases this results in making it 

 appear that the last author changed the immediately preceding name, 

 whereas his change may have been in relation to a still earlier one. 

 When it is essential to determine this point, examination of the last 

 publication involved usually will settle the matter. 



A few new synonyms and other nomenclatorial changes have been 

 presented on the basis of my personal knowledge or of information com- 

 municated by Drs. N. B. Causey and R. L. Hoffman, credit for such 

 information being shown in each case. 



The depository of the holotype specimen of each species is named 

 wherever possible. Dr. Hoffman graciously assumed the task of supplying 

 the name of the depository of all species where the author could not do 

 so. His familiarity with milliped types seen during past visits to European 

 museums greatly aided in this and the many names he supplied are all 

 followed by his parenthesized last initial. 



Because so few of the species are known from more than one or two 

 localities, no general statements on distribution have been given. Instead, 

 type and paratype localities are shown, and all other published localities 

 are listed, with tlie name of the recorder and the place of record indi- 

 cated as for other bibliographic citations. 



