ADVERTISEMENT 



The scientific publications of the National Museum 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 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 present volume is the ninetieth of this series. 



The series of Bulletins^ the first of which was issued in 1875, con- 

 tains separate publications comprising monographs of large zoologi- 

 cal groups and other general systematic treatises (occasionally in 

 several volumes), faunal 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 

 were regarded as indispensable. In the Bulletin series appear vol- 

 umes under the heading Contrihution.s from the United /States National 

 Her-harimrb^ in octavo form, published by the National Museum since 

 1902, which contain papers relating to the botanical collections of 

 the Museum. 



AlJEXANDER WeTMORE, 



Assistant Secretary^ Smithsoniun Institution. 



