advertisp:mp]nt. 



This work (Bulletin N<». 41) is one of a series of papers intended to 

 illustrate the collections belonging to the United States, and constitu- 

 ting- the National Museum, of which the Smithsonian Institution was 

 placed in charge by the act of Congress of August 10, 1846. 



The x>nblications of the National Museum consist of two series — the 

 Bulletins, of which this is No. 41, in continuous series, and the Proceed- 

 ings, of which the fourteenth volume is now in press. A small edition 

 of each paper in the Proceedings is distributed in pamphlet form to 

 si)ecialists in advance of the publication of the bound volume. 



The Bulletins of the National Museum, the publication of which was 

 commenced in 1875, consist of elaborate papers based upon the collec- 

 tions of the Museum, reports of expeditions, etc., while the Proceedings 

 facilitate the prompt publication of freshly accpiired facts relating to 

 biology, anthropology, and geology, descriptions of lestricted groups of 

 animals and plants, the discussion of ])articular questions relative to 

 the synonymy of species, and the diaries of minoi' expeditions. 



Other i^apers, of more general pijpular interest, are printed in the 

 Appendix to the Annual Keport. 



Full lists of the publications of the Museum may be found in the cur- 

 rent catalogues of the publications of the Smithsonian Institution. 



Papers intended for publication in the Proceedings and Bulletins of 

 the National Museum are referred to the CommittcH* on Publications, 

 composed as follows : T. H. Bean, A. Howard Clark (editor), P. E. 

 Earll, Otis T. Mason, John Murdoch, Leonhard Stejneger, Frederick 

 W. True, and Lester F. AVard. 



^ S. P. Langley, 



Secretary of the Smithsonian InstitHtion. 



Washington, 1). C, May 28, 1891- 



