ADVERTISEMENT 



The scientific publications of the National IMiiseum include two 

 series, known, 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 collec- 

 tions of the National Museum, that set forth newly acquired facts 

 in biology, anthropology, and geology, with descriptions of new 

 forms and revisions of limited groups. Copies of each paper, in 

 pamphlet form, are distributed as published to libraries and scientific 

 organizations ajid to speciahsts and others mterested in the different 

 subjects. 



The dates at v/hich these separate papers are published are recorded 

 in the table of contents of each of the volumes. 



The Bulletin series, the first of which was issued hi 1875, consists 

 of separate publications comprising monographs of large zoological 

 groups and other general systematic treatises (occasionally in several 

 volumes), faunal works, reports of expeditions, catalogs of type speci- 

 mens and 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 wliich large plates were regarded 

 as indispensable. In the Bulletin series appear volumes under the 

 heading Contributions from the United States National Herbarium, in 

 octavo form, pubhshed by the National Museum since 1902, which 

 contain papers relating to the botanical collections of the Museum. 



The present volume forms No. 171 of the Bulletin series. 



Alexander Wetmore, 

 Assistant Secretary , Smithsonian Instiiuiion. 



Washington, D. C, January 25, 1938. 



