ADVERTISEMENT. 



This work (Special Bulletin No. 1) is one of ;i scries of papers intended to 

 illustrate the collections belonging to, or placed in charge ot, the Smithsonian 

 Institution, and deposited in the U. S. National Museum. 



The publications of the National Museum consist of two series : the Bulletin 

 and the Proceedings. A small edition of each paper in the Proceedings is 

 distributed in pamphlet form to specialists in advance of the publication of the 

 bound volume. The Bulletin is issued only in volumes. Those hitherto pub- 

 lished have been octavos, but it has been decided that for works of the size and 

 character of the present Bulletin the quarto form is preferable. 



The Bulletin of the U. S. National Museum, the publication of which was 

 commenced in 1875, consists of elaborate papers based upon the collections of the 

 Museum, reports of expeditions, etc. The Proceedings are intended to facilitate 

 the prompt publication of freshly acquired facts relating to biology, anthropology, 

 and geology, descriptions of restricted groups of animals and plants, discussions 

 of particular questions relative to the synonymy of species, and the diaries of 

 minor expeditions. 



( Mher papers of more general popular interest are printed in the appendix 

 to the annual report 



Full lists of the publications of the Museum may be found in the current 

 catalogue of the publications of the Smithsonian Institution. 



Papers intended for publication in the Proceedings and Bulletin of the U. S. 

 National Museum are referred to the Advisory Committee on Publications, com- 

 posed as follows: T. II. Bean (chairman), A. Howard Clark, R. E. Earll, Otis T. 

 Mason, Leouhard Stejneger, Frederick W. True, and Lester F. Ward. 



S. P. LANGLEY, 



, Swrrlttn/ of the Smithsonian Institution. 



WASHINGTON. DC, M,,,/ /;, 



