24 REPORT OF THE SECRETARY. 



Review of American Birds in the collection of the Smithsonian 

 Institution. By S. F. Baird. Pp. 143-320 or 172 pp. (Published 

 May, 1865.) 



Researches upon the Hydrobiinse and allied forms, chiefly made 

 upon materials in the museum of *the Smithsonian Institution. By 

 Dr. W. Stimpson. Pp.64. (Published August, 1865.) 



In addition to the above, continuations of the following works 

 were printed in 1865: 



Catalogue of transactions of societies and scientific journals in the 

 library of the Smithsonian Institution. 200 pp. 



Continuation of Parts II and III, by Mr. Binney, of the Synopsis 

 of the Land and Fresh Water Shells of the United States. About 

 60 pp. 



These make a total of 514 pages, and, including the Annual Report 

 of 1864, (450 pages,) an aggregate of 964 octavo pages • and of all 

 classes of publications, 1,672 pages. 



Smithsonian Contributions. — The first paper which has been re- 

 ceived for publication in the quarto series, and which has not yet 

 been described, is that on the planet Neptune, by Professor New- 

 comb, of the National Observatory. 



It will be recollected by those who are familiar with the history of 

 the operations of the Institution, that shortly after the discov^ery of the 

 planet Neptune, the first ephemeris of, or, in other words, a table for 

 indicating, its position in the heavens at any time during the year was 

 prepared and published at the expense of the Smithsonian fund. This 

 ephemeris was computed from an orbit based on a remarkable dis- 

 covery of Professor Sears C. Walker, then of the Washington Obser- 

 vatory. Beginning with observations of the movement of the planet 

 during a period of four months, Mr. Walker traced its path among 

 the stars through its whole revolution of 166 years, and was thus 

 enabled to carry its position backward until it fell among a cluster of 

 stars, each of which had been accurately mapped by the celebrated 

 Lalande, near the close of the last century. From a critical scrutiny 

 of these stars, Mr. Walker was led to conclude that one of this clus- 

 ter observed by Lalande on the night of the 10th May, 1795, was the 

 planet Neptune. Availing himself of this discovery, Mr. Walker 

 had now a series of observations, embracing not merely a few 

 months of the movement of the planet, but its entire motion during 

 a period of fifty years. From these data he was enabled to deduce 

 a perfect elliptical orbit, or one which the body would describe were 



