ADVERTISEMENT. 



The Scientific publications of the National Museum consist of two 

 series — Proceedings and Bulletins. 



The proceedings, the first volume of which was issued in 1878, are 

 intended primaril}- as a medium for the publication of original papers 

 based on the collections of the National Museum, setting forth newly, 

 acquired facts in biology, anthropology, and geology derived there- 

 from, or containing descriptions of new forms and revisions of limited 

 groups. A volume is issued annually or oftener for distrilnition to 

 libraries and scientific establishments, and, in view of the importance 

 of the more prompt dissemination of new facts, a limited edition of 

 each paper is printed in pamphlet form in advance. The dates at 

 which these separate papers are published are recorded in the table of 

 contents of the volume. 



The present volume is the thirty-third of this series. 



The Bulletin, publication of which was begun in 1875, is a series of 

 more elaborate papers, issued separately, and, like the Proceedings, 

 based chiefiy on the collections of the National Museum. 



A quarto form of the Bulletin, known as the "Special Bulletin," has 

 been adopted in a few instances in which a larger page was deemed 

 indispensable. 



Since li»02 the volumes of the series known as "Contributions from 

 the National Herbarium," and containing papers relating to the botan- 

 ical collections of the Museum have been published as Bulletins. 



Charles D. Walcott, 

 Sec7'eta7'y of the Sinithaoiifan Institution. 



March 16, 1908. 



