advp:rtisement. 



The extensiou of the scope of the National Museum duiiug the past 



■few years, and the activity of the collectors employed iu its interest, 



have caused a great increase iu the amount of material in its possession. 



Many of the objects gathered are of a novel and important character, 



and serve to throw a new light upon the study of nature and of man. 



The importance to science of prompt publication of descriptions of 

 this material led to the establishment, in 1878, of the present series of 

 publications, entitled "Proceedings of the United States National 

 Museum," the distinguishing peculiarity of which is that the articles 

 are i)ublished in signatures as soon as matter sufticient to fill sixteen 

 pages has been obtained and printed. The date of publication being 

 plainly expressed on each signature, the ready settlement of questions 

 of priority is assured. The present volume constitutes the tenth of the 

 series. 



The articles in this series consist : First, of papers prepared by the 

 scientific corps of the National Museum ; secondly, of papers by others, 

 founded vipon the collections iu the National Museum ; and, finally, 

 of interesting facts and memoranda from the correspondence of the 

 Smithsonian Institution. 



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

 commenced in 1875, consist of elaborate papers (monographs of families 

 of animals, etc.), while the present series contemplates the prompt pub- 

 lication of freshly-acquired facts relating to biology, anthropology, and 

 geology 5 descriptions of restricted groups of animals and plants ; the 

 settlement of particular questions relative to the synonymy of species; 

 and the diaries of minor expeditions. 



The Bulletins and Proceedings are published by the authority and at 

 the expense of the Interior Department, and under the direction of the 

 Smithsonian Institution. 



Papers intended for publication in the Proceedings and Bulletins of 

 the National Museum are referred to the Committee on Publications, 

 composetl as follows: T. H. Bean, A. Howard Clark (editor), Otis T. 

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



S. P. Langley, 



* Secretary of the Smithsonian Institution. 



United States National Museum, 



Washington, March 1, 1888. 

 II 



