ADVERTISEMENT. 



The publications of the Natiomil Museum consist of two series: 

 Proceedings and Bulletins. 



The Proceeding-s, the first volume of which was issued in 18TS. are 

 intended primarily as a medium of pu))lication for newly acquired 

 facts in biology, anthropology, and geology, descriptions of new forms 

 of animals and plants acquired ))y the National Museum, discussions of 

 nomenclature, etc. A volume is issued ammally or oftener for distri- 

 bution to libraries, while in view of the importance to science of the 

 prompt publication of descriptions of new species, a limited edition of 

 each paper is printed in pamphlet form in advance. 



The present volume is the twenty-seventh of the series. 



The Bulletin. pul)lication of which was begun in 1875, is a series 

 of more elaborate papers, issued separately and based for the most 

 part upon collections in the National Museum. They are mono- 

 graphic in scope, and are devoted principally to the discussion of 

 large zoological groups. l)ibliographiesof eminent naturalists, reports 

 of expeditions, etc. 



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

 been adopted in a fcAV instances in which a larger psige was deemed 

 indispensable. 



The Annual li(^port of the National ^Museum (l)eing the second vol- 

 ume of the Smithsonian Report) contains papers chiefly of an ethno- 

 logical character, describing collections in the National Museum. 



Papers intended for publication l)y the National Museum are usually 

 referred to an advisory conuuittee, composed as follows: Frederick 

 AV. True (chairman), William H. Hohnes, George P. Merrill. James 

 E. Benedict, Otis T. ]\Iason, Leonhard Stejneger, Lester F. Ward, 

 and Marcus Benjamin (editor). 



S. P. Langley, 

 Secretary oftJie SiiiffJts{»)ian Lh-<t!tut!on. 



