VIII 



PREFACE. 



and this is now considered as the first of a set of Smithsonian Reports. 

 The number of pages was limited between 1854 and 1876 to 400. In the 

 latter year this restriction was removed, and since then the average number 

 of pages has been 600. 



The number of copies of these reports for general distribution ordered 

 by Congress has been very variable, the largest being 7,500 in 1874 and 

 1875, and the smallest 150 in 1847. The number of copies granted the 

 Institution each year is shown in the following table: 



Ntimber of extra copies furnished the Institution by Congress for distribution. 



The total number of pages in the 35 volumes of Annual Reports is 14,419, 

 average 412 pages; total number of woodcuts, 1,898. 



4. Bulletins of the U. S. National Museum. 



In the year 1875 a fourth scries of publications (octavo) was commenced, 

 entitled " Bulletins of the National Museum," intended to illustrate the col- 

 lections of natural history and ethnology belonging to the United States, 

 constituting the National Museum, of which the Smithsonian Institution is 

 the custodian. 



Twenty of these Bulletins have been published, with an aggregate of 3,103 

 pages, 45 plates, and 1 map. 



