LHTTER OF TRANSMITTAL 



Smithsonian Institution, Bureau of Ethnology, 



Washington, D. C , July 1, 1891. 

 Sir: I have the honor to submit my twelfth annual I'eport 

 as Director of the Bureau of Ethnology. 



The lirst part consists of an explanation of the plan of the 

 Bureau and its operations during the fiscal year 1890-91 ; the 

 second part comprises an extended paper on the mound explo- 

 rations of the Bureau of Ethnology, giving an example of the 

 methods and results of the work of the Bureau relating to the 

 important branch of archeology indicated. 



I desire to express my thanks for your earnest support and 

 your wise counsel relating to the work under my charge. 

 I am, with respect, your obedient servant, 



Hon. S. P. Langley, 



Secretary of the Smithsonian Institution. 



