ADVERTISEMENT 



The scientific publications of the National Museum include two series, 

 knowTi, respectively, as Proceedings and Bulletin. 



The Proceedings series, begun in 1878, is intended primarily as a medium 

 for the publication of original papers, based on the collections of the 

 National Museum, that set forth newly acquired facts in biology, anthro- 

 pology, and geolog3^, with descriptions of new forms and revisions of limited 

 groups. Copies of each paper, in pamphlet form, are distributed as pub- 

 lished to libraries and scientific organizations and to specialists and others 

 interested in the different subjects. The dates at which these separate 

 papers are published are recorded in the table of contents of each of the 

 volumes. 



The series of BuUeiins, the first of v/hich was issued in 1875, contains 

 separate publications comprising monographs of large zoological groups 

 and other general systematic treatises (occasionally in several volumes), 

 fauna! works, reports of expeditions, catalogs of type specimens, special 

 collections, and other material of similar nature. The majority of the 

 volumes are octavo in size, but a quarto size has been adopted in a few 

 instances in which large plates v/ere regarded as indispensable. In the 

 Bulletin series appear volumes under the heading Contributions from the 

 United States National Herbarium, in octavo form, published by the National 

 Museum since 1902, which contain papers relating to the botanical collec- 

 tions of the Museum. 



The present work forms No. 185 of the Bulletin series. 



Alexander Wetmore, 

 Assistant Secretary, Smithsonian Institution. 

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