ADVERTISEMENT. 



The present work is a catalogue of that portion of the Library 

 of the Smithsonian Institution which embraces the publications 

 of learned societies and other public bodies, as well as encyclo- 

 paBdias and periodical and serial works in general. It also 

 includes the titles of periodicals in possession of the Institution, 

 published by private parties, particularly those relating to the 

 Natural and Physical Sciences. A separate catalogue of mono- 

 graphic works in the Library will hereafter be issued. 



Most of the works in this portion of the Library of the 

 Smithsonian Institution have been obtained in exchange for its 

 own publications, and the number it is hoped will continue to 

 increase through the same agency. 



The printing of this work was begun in 1863 and completed 

 in 1866. During its passage through the press many additions 

 to portions already printed have been received, which will be 

 hereafter embodied in an appendix, Intended to bring the cata- 

 logue down to the latest date. With this object each Institution 

 in correspondence with the Smithsonian Institution will receive 

 the portion relating to its own publications, corrected in manu- 

 script to date of transmission, and it is respectfully and earnestly 

 requested by the Institution that the series be made as complete 

 as possible. 



By a comparison of the present work with the catalogue of 

 1858, it will be observed that this portion of the Library has 

 been increased more than threefold in the eight years that have 

 elapsed since that time. 



In view of the deficiency of proper accommodations for the 

 rapidly increasing Library of the Institution, resulting from the 

 destruction of a portion of the building by fire in January, 1SG5, 

 a law has been passed by tiie Congress of the United States, 

 authorizing its deposit iu tlie ne\v fire-proof Library rooms of 



